Selasa, 15 April 2014

Understanding Hydroponics

This instructable will explain household hydroponics, with the intention of growing edible flora. 
In layman's terms, hydroponics is the science of growing plants without soil-- although the plants may or may not be suspended in a solid medium such as gravel, or expanded clay balls.
Soil retains minerals and nutrients, which "feed" flora, as we all know. Plant roots can't absorb dirt, however; when water passes through soil, it dissolves and collects some of the nutrient particles embedded. This "food" solution is absorbable as a liquid. As you can see, the soil itself is not an integral part of a plant's feeding cycle-- it is simply a stabilizer for the roots, and a convenient filter.

Why eliminate the soil?
Plants breathe air, just like humans. School children are taught a simple lesson: plants take in carbon dioxide, and release oxygen. The entire plant-- not just leafy material-- contributes to this process.
If not properly maintained, soil can retain too much moisture, effectively suffocating ("drowning") a plant's root system. Alternatively, if the soil doesn't contain enough moisture, the plant will be unable to absorb the nutrients it needs to survive.
The roots of a hydroponic plant have constant access to both air and water, and it can be much easier to maintain that balance since the roots are typically visible.
The average plant needs at least five things to survive. Air, water, nutrients, minerals, and light. So long as you can provide these things in plenty, your plants should stay healthy.

Growing your own food can be a rewarding experience. It's a good way to save money on pesticide-free produce, and you'll know it wasn't shipped from a third-world serf farm supporting bad business. If your hydroponic system is indoors, you can grow food during the off-season in winter, too.

That being said, there may be more efficient systems out there for the home grower. I created this instructable to inform, more than anything.
After all, if anything's worth doing, it's worth doing right. Gotta do your research, kids.
Remove these adsRemove these ads by Signing Up

Step 1: Substrate 101

Although not necessary for the survival of a plant, substrate can help to support a plant physically and hold it upright, either by securing the root system, or by outweighing the plant itself. There are many kinds of substrates commercially available. Check your local greenhouse or hardware store. Alternatively, there are plenty to be found outdoors, especially near bodies of water.
Even simple rock can alter the PH of your system. When checking your PH balance, be sure to check it after it has circulated through your substrate.

In the moisture-rich conditions hydroponics typically provide, substrate can be generally classified into the following categories: sandy, granular, and pebbled.

Sandy environments consist of particles between .06 (fine) and 2mm (coarse) in diameter. Even coarse sand retains a considerable amount of water (except in comparison to soil), and is not generally considered appropriate for use in a hydroponic system. If you use a pump, for example, the small particle size may lead to clogging. However, it is cheap and readily available, and, when wet, is heavy enough to provide a reasonable anchor for plant roots.
There is some absorbable nutrient in sand. Typically speaking, the nutrients latent in sand culture vary widely on the substrate's color and origin. Most sand contains a large quantity of shell fragments, and thus has a high calcium content.
Black sand usually has a high magnetite content originating from volcanic rock, known for its fertility. Orange or yellow sand might be an indicator of a high iron content.
White sand tends to be very high in silica, which helps build healthy cell walls in plantlife. Diahydro, for example, is made from diatoms, a type of algae.
Sand is semi-reusable. Sterilizing it between uses can be messy. (Sand can be sterilized by boiling it in water for extended periods of time.)

Granular particles range between 2 and 4mm. This may consist of gravel, or plant mulch.
Stone gravel makes a heavy, non-biodegradable anchor for plant roots, and is highly recommended for use in hydroponic systems. Stone gravel contains very little latent plant nutrition, just like sand. There are several grades of gravel readily available to choose from.
Creek rock and Pea Gravel consist of round, shiny stones. The smooth shape of these stones allows for great aeration and root growth, although the drainage may be excessive.
Crushed rock is typically made by crushing large chunks of limestone or dolomite into smaller pieces. Crushed rock has sharper edges than creek rock, and tends to interlock better. This tighter knit makes for higher water retention, although limestone tends to weigh less. Limestone is a strong alkali. Check your PH, and balance accordingly.
Stone-based substrate is highly re-useable. It is considerably less messy than sand to boil for sterilization.
If weight is not a concern (ie: the plants you grow are not expected to reach considerable heights) you might consider using a plant mulch, such as peat mulch, cedar shavings, or coir (coconut peat). Mulches retain a high quantity of water, but also breathe very well. Mind you, they are also highly degradable, which can lead to clogged pumps, and wood shavings often contain aromatic oils which can inhibit plant growth. Mould and algae growth poses a higher risk when mulches are involved, but pose one considerable advantage over rocky substrate: they can be composted and replaced with fresh material. It does not need to be stored. I would n't suggest re-using 'em, anyway. This is especially convenient if you use hydroponic systems exclusively to start seeds, or grow during the off-season.

Pebbled substrate measures between 4 and 64mm.
Stone pebbles have the basic characteristics of creek rock. They are typically smooth, often shiny, and the gaps between the stones make for low water retention and high aeration. The shinier the stone, the worse the water retention will be. A matte or pockmarked surface indicates a porous stone, which will stay damper, longer, whilst still providing excellent aeration. Pebbles-- especially the porous variety-- can explode when heated for sterilization.

A common alternative to these substrates is mineral (rock) wool. You've probably seen it used as insulation in housing. Rock wool contains fiberglass, and it can be absorbed into the body by inhalation-- irritating eyes, skin, and lungs. It needs to be treated before it is a tolerable substrate for plant growth. Altogether, I don't recommend its use.

As I've said, you should boil your substrate between uses to sterilize it. Bacteria love warm, wet environments and will probably thrive in a hydroponic system.
Just a heads-up, here... algae loves wet and warm (and lukewarm... and cold) systems, too, and it can look unsightly. If you care about appearances, boiling your substrate between uses will discourage blossoming, but if you use grey (recycled from previous use) water you'll be fighting a losing battle.

Step 2: Plant Food 101

This article discusses nutrient solutions available for hydroponic gardening.

Water alone is not enough to feed a plant. Distilled water, in particular, lacks the minerals and nutrients which make flora thrive.
In systems where the substrate is allowed to moisten and support roots, the substrate itself may be permeated with nutrients and minerals. In systems where there is no substrate, or the substrate is simply provided to support the plant physically, the water must be saturated with store-bought or homemade nutrient-and-mineral solutions.

The PH of your solution is important for the health of your flora, and the maintenance of your equipment. Your water/nutrient solution should have a final PH between 6.0 and 7.0.
These solutions usually contain varying quantities of potassium nitrate, calcium nitrate, potassium phosphate, magnesium sulfate, iron, manganese, copper, zinc, and nickel. Potassium, especially, assists with healthy root growth. Salt is an important (but often forgotten) addition to the solution, as it tends to improve the taste of the plants grown.

Store-bought liquid-soluble fertilizers are readily available at your local big-box greenhouse, nursery, or hardware store. They work well enough, but they can be expensive, or simply may not be available.

The rest of the article will discuss making your own fertile solution.

A popular, homemade recipe consisting of accessible ingredients is available at your disposal. I daresay it's not the most eco-friendly option, but it's quick and easy. For every gallon of water your system requires, add two teaspoons of Miracle Gro and 1 teaspoon of epsom salts.

I've always found semi-symbiotic relationships both fascinating and convenient.

On a controversial note, human urine can be used as a nutrient solution. Remember, the body filters everything you eat and drink, expelling toxins and retaining the essentials. If you eat something slathered in pesticides, you'll be urinating it out later. If you use that urine to grow spinach, you'll re-absorb it when you eat it. There are risks involved. Do your research.
You'll need to have a sample of your pee tested by a floraculture lab, of course, so you may need to adjust your diet. Vegans will find their urine more appropriate for plant growth than their animal-product-eating companions.
If the plants you are growing are intended for consumption, you will need to find a way to treat and sterilize your urine, making it less of a biohazard. Introducing nitrous bacteria, and diluting the solution, will help break down the ammonia prevalent in your urine. Circulating it through a biofilter will do this. Alternatively, you may be able to find an ammonia treatment in your local aquarium store.
Wanna learn how to build a biofilter? I'll get back to you on that one.

You might consider using your hydroponic system in lieu of a filter for a fish tank, hooking up a circular system filtering fish water through various substrates. There are three kinds of filter medias used in household tanks-- mechanical, biological, and chemical.
Mechanical media is used to filter out solid matter-- chunks of substrate, algae scrapings, what have you. Sponges and fibrous materials (rock wool, for example) work admirably in this fashion. Consider inserting a sponge or somesuch in each plant's drain, to reduce the risk of clogging your system, at the very least.
Biological filters are meant to encourage colonies of healthy bacteria, and control levels of ammonia, nitrites and nitrates prevalent in fish waste. Your plants will be glad to serve this function.
Chemical filters clean your water of unwanted color and odor. Unfortunately, it also excels at removing the trace elements which allow plants to thrive. You won't need it.
If you already have a fishtank, you could simply use the water you would normally siphon off and discard during cleaning, and use it to top off your hydroponics system. If your fishtank filtered, you'll have limited success with this technique.

In the meantime, consider this: a successful hydroponics system will grow plenty of plant matter, and much of it will be consumed. What little waste there is, could be recycled back into the system (accompanied by other waste matter) with the help of another animal: the worm.


Vermicomposting is a composting technique in which live worms are used to turn food waste into fertile soil. A handy by-product of the process is a nutrient-rich liquid commonly referred to as "worm tea".
Obviously, this bin won't be for composting materials from your hydroponic system exclusively-- your kitchen scraps should go in, too. Waste not, want not!

Vermicompost can be suitable for indoor and outdoor composting. If maintained properly, a good vermicompost system will not stink the same way traditional compost can. The ammonia smell we commonly associate with compost is only prevalent when the wet waste content (rotting detritus) of the bin overexceeds the dry matter (paper or plant fiber) mixed in. Worms-- red wrigglers in particular-- like to have soft, dry bedding like shredded paper or coconut fiber available to them, anyway. A stinky bin usually means unhappy worms.

There are many ways to compost in this fashion, however, for the intentions of this instructable, we will focus on the relatively uncomplicated "non-continuous" vermicompost bin.
This system is usually very small and easy to build, but if you plan on using the worm castings as well as the worm tea, you'll need to dump out the whole container after draining it. I would highly recommend transferring your worms and a small portion of the castings to another vermicompost system of any other build type, after dumping.

In order to harvest liquid worm tea (instead of distilling it from worm castings in a water bath) you will need a large plastic bucket with a draining tap and a lid. Plastic is nonporous, unlike wood, so it shouldn't absorb the valuable tea. That old, giant thermos football players bully their waterboys around would do the trick nicely.
Non-continuous systems like this can be very simple-- they're just an undivided container layered from the bottom up as follows: sump, bedding, worms, wet waste, dirt.
The bottom layer-- the sump-- should consist of a two-inch deep level of small stones and gravel. This area will be rife with crevices liquid can settle into, to drain at your convenience. A layer of fine mesh should be placed over this level to prevent the worms and their solid castings from falling into the sump. Mesh should not be placed between any other levels.
Worm bedding, as mentioned earlier, is typically three inches of loosely-packed shredded paper or coconut fiber. This level will help aerate the mixture, lower fragrant nitrogen levels, and allow your worms to thrive.
Your wet waste should never include meat or dairy product like cheese or yoghurt. Frankly speaking, those things stink when they decompose, which they do quickly because of their high protein content. Genuinely putrid food is toxic to worms. Beans are also high-protein, and dangerous as such. Oils and fats prevalent in animal products will cling to the skins of your wrigglers and suffocate them.
Stick to eggshells, tea bags, vegetable peels, stale/mouldy bread, coffee grounds, rotting fruit, etc. Citrus fruit is generally considered safe, but not citrus peel-- the oil found in the skins are toxic. Banana peels are usually heavily sprayed with herbicides and pesticides, so include them at your own peril. Worms are highly sensitive to poison.
Wet waste should be covered with another layer of bedding, for odor control.

As the worms eat the rotting material, add wet waste to the top level, sprinkling with shredded paper as you go. The worms will consume what they can, and then travel up out of their castings (urine and feces) and into the new feed. Continue the process until the bin is full, and most of the edible matter has been turned into castings by the worms. Drain the sump whenever your hydroponic system requires more fertilizer.
Make sure you test the water's final PH, and adjust accordingly!

Step 3: Lighting 101

In nature, plants photosynthesize white light from the sun. Sunlight is free. Use it where and when you can.
There's no reason you can't build your system outside, after all, climate permitting. Alternatively, consider placing your hydroponic system in a room with plenty of natural lighting.
If you live in the north hemisphere, for example, your south-facing rooms typically get the most light over the course of the day. Put it there.

During the winter, even in areas where the temperature is tolerable year-round, the sun's light is weak, and plants will suffer. Besides, hydroponic systems are typically indoors where location limits proper daytime lighting to two or three hours in the middle of the season.

You can help mother nature along by using artificial light.

Artificial grow-lighting kits can be purchased in stores, or built on a budget at home. The cost will depend heavily on how many plants you plan to be lighting.
Frankly, you can expect to lay down at least $100 to light a very small area-- we're talking a meter squared, here.
Plants absorb red and blue light wavelengths efficiently, which stimulates growth. More importantly, plants absorb one more than the other. Whether you buy or build your grow lights, you should be looking for an 8-1 ratio of red and blue emitters. (8 red for every blue, not vice-versa.)
Although green lights are commonly included in standard grow light kits, they're not considered "necessary". Green light is mostly reflected, producing the vibrant color we associate with healthy leaves. Grown without green light, plants take on much darker shade-- almost black-- and rumor has it they take on different flavor characteristics. However, if energy consumption is a concern (this is a budget-saving project, after all) eliminate the green light, but not the blue or red.

LEDs are highly recommended for hydroponic projects, considering the serious advantages they hold over traditional halogen bulbs. They have much longer life-spans, produce less heat and consume less energy. For bonus eco-points, power your LEDs with solar chargers!
Consider the cost of the LEDs to be an investment towards lower energy bills (especially in comparison to operating halogen grow lights) and smaller grocery tabs.
There is one major drawback to using LED lighting, besides the cost. (Derrekito brought this up on another instructable.) The average plant absorbs is happiest absorbing red light at 600-625nm. The average red LED emits light at about 630-660nm.
LED lighting isn't perfect. I highly recommend supplementing with natural light.

I am not the person to ask about building LED grow-light systems. There are plenty of existing instructables available on the subject. Instructable's own }{itch seems to know his stuff. Look'im up.

Step 4: Irrigation 101

In hydroponics, water can be delivered to a plant via local irrigation, or sub-irrigation.
Local irrigation is a general term, describing the process of piping small amounts of water to individual plants. Typically this water is administered at the surface level. Drip and sprinkler irrigation works in this manner.
Sub-irrigation simply refers to any system which forces water to be absorbed from the bottom of a root system, to travel upwards-- wicking techniques partially submersing the roots or substrate of a plant are common.
Water is a valuable commodity. If you can, be eco-friendly by collecting rain or melted snow. As mentioned previously, siphoning used aquarium water from your fishtank in lieu of a filter will provide a nitrate-rich nutrient solution for your plants and the moisture they need to survive. There are lots of green alternatives to treated tap water.

Well, that's it for now. I'll add more detailed instructions and expound on the subject further, as inquiries are made. In the meantime, you folks can consider starting (or expanding on) your own projects, armed with a better understanding of the subject.
And knowing is half the battle, eh?
Have fun.

My First Hydroponic Plant (Beginner's Guide)

Start your very first miniature hydroponic plant! A recommended guide for beginners who both loves planting and technology. I'm going to show you how to make one in less than 15 minutes, out of household materials! Our tiny "Hydroponic System" kinda cost us $5-7.
Since our goal is to make this eco-friendly we hooked it to my 3W solar panel + powerbank, similar to my "Portable Solar Charger" guide. This guide is great for school projects such as: science fair and investigatory projects

Our Investigatory Project (GRADE 8 - IP):
Originally this project was documented for our "Investigatory Project" last year, about: "The Feasibility Of Growing Crops In A Hydroponic System" Our . I.P. was quite a success, caught some attention and got the highest grade in class.

So the problem goes like this: Today’s rapid growth of human population causes the lack of available space for crop agriculture. The traditional method for planting crops requires labor intensive methods such as:  tilling lands, watering crops on a daily basis, using unhealthy pesticides, fumigating the crops. Scientists say that “vertical farming” is the future of plant agriculture, although soil is very hard to transport, especially in tall building. Hydroponics  is done to have better control of the nutrients being absorbed by the plants and makes planting on rooftops more convenient and easier
Recommended Seeds/ Plants:
- Tomato Seeds/ Plant
- Mung Beans/ Plant (We used this one)
- Chili Pepper
- Bell Pepper

Step 1: Gathering Your Tools And Materials

Parts & Materials: (Some links are just alternative, I bought mine for $5)

- Recycled Container (Free)
Controlled Fertilizer ($1.00)
DC Water Pump ($4.00)
A Cheap Mini Funnel ($0.10)
Aquarium Tubing ($0.40)
Water Flow Valve ($0.20)
- T-Shaped Splitter ($0.10)
- Super Glue/ Epoxy ($1.00)

Recommended Pump Kit: DIY Water Pump Motor Water Pipe Power Supply Set ($12.90)

Tools & Equipment:

- Leatherman Multitool (Gift From: Instructables)
- Rotary Tool (Dremel/ Black & Decker)
- Permanent Marker
- Soldering Iron
- Hot Glue Gun
- 12inch Ruler

Step 2: Installing The Water Distribution System In Your Funnel

Our hydroponic setup uses a simple water drip system. Water needs to reach the plant, also needs to get distributed evenly.

1st.)  Drill a hole on your funnels side for the T-splitter.
2nd.) Measure the inner circumference of your funnel and cut a strip of tube [Formula: (2)(π)(r)]
3rd.)  Slit some hole on your tube using a knife, be sure to slit it on 5 even sides. Use a ruler!
4th.)  Connect your tube on the T-shapped splitter
5th.)  Apply a few drops of super glue to mount your assembled drip system (tube) on your funnel

Step 3: Glue The Assembled Funnel To The Cover

This is a three step procedure, be careful in handling knives and hot-glue.

1st.)  Trace your funnel on top of your container's cover
2nd.) Use your leatherman's knife  to cut a hole cleanly
3rd.)  It's now time to warm up your gluegun and mount the funnel to your container's cover. Be sure to seal in the gaps!

Step 4: Installing Your Water Pump

There are some factors to consider in buying water pumps, the AC (outlet type) consumes a lot electricity and isn't compatible with solar panels, the DC (battery type) can be easily hooked to a solar panel w/battery, providing free electricity 24/7.

If you plan to hook it up to a solar panel, I recommend reading:  DIY Portable USB Solar Charger ($20)

Okay lets get started! What I have here is a non-submersible water pump, which I found from my inventory. I had to drill a hole on the container in order to add a pinch valve (water flow valve). The pump is slightly elevated since it is not water proof. 

Step 5: Finalizing The Setup

I saw this pack of fertilizer lying around my our garden, it was my dad's. It's a typical complete & controlled fertilizer for general purpose. For my setup, I just dropped 2 table spoons of fertilizer. If your concerned for your plant's nutrition, there are some fertilizers designed for hydroponic setups found in

Use smooth pebbles to hold your plant's roots, make sure they are tucked in firmly.

Step 6: Soil Planting Vs. Hydroponics

Here's the result of our experimentation for our investigatory project (school project). You can find a significant difference between the soil plant and the hydroponic plant. The hydroponic plant started as the underdog. As time goes by, it managed to surpass the growth of the soil planted plant.

Small NFT Hydroponics System

Hydroponics is a type of agriculture that uses no dirt, and usually results in larger, fuller plants. I recently became interested in the topic, and decided to start my own vegetable garden using the Nutrient Film Technique (NFT). It involves a channel of nutrient enriched water constantly flowing past a plant's roots. The system that I'm demonstrating here is just one example of infinitely many possibilities. Take my work and use it as inspiration for developing a system that suits you and your needs.

Step 1: The Idea

Because hydroponics requires a resevoir for water to be drawn from and returned to simultaneously, and I was just building a small system, my design has two gullies. This allows the water to easily go full circle.

Along with the water pump, my system uses gravity to assist the flow of water. Each end of the PVC is one inch higher than the end that comes next in the circle. The end of the tube that water enters from is the highest, and the end that it leaves from is the lowest. To achieve this, I built supports out of lumber for the pipes. The supports also keep them high enough to be above the reservoir, so that gravity will return the water to it.

Step 2: Materials

  • 66" of 4" PVC Pipe - If I didn't already have PVC, I would have probably bought plastic gutters.
  • Assorted lumber - Go to the cull wood section of your hardware store. This is the wood they cut for other people who didn't want the scraps. I got four 43" 2x4"s, one 1.5x7.5x58" piece, and a scrap of plywood for $3.
  • Screws and such
  • 4 rubber adjustable end caps with hose clamps - about $3 each
  • Submersible pump - I'm using this
  • Teflon tape
  • 16 oz Plastic cups
  • Plants
  • Irrigation tubing
  • Opaque Bucket
  • Plumbing cement
  • Growing medium - I used expanded clay ball
  • Hydroponics Nutrient
I would make a list of tools, but there's no way I could make an exhaustive list.

Step 3: Build the stands

Once you figure out the height of your reservoir, you can start designing your stands. Mine is about 13" tall, so my stands are 13", 14", 15", and 16". After cutting the lengths, I cut a triangle (with a height of 2.5") out of each one to hold the PVC.

I'll assume you've already cut the PVC in doesn't really deserve it's own step.

Next, I attached them together with the 2x4's. I found out the hard way that it's easier to make them level if you attach the 2x4's mid way up, instead of at the bottom.

Step 4: Plumbing

You'll need to drill a hole with a spade bit suitable for your tubing in each of the end caps. Drill the holes at the height that you want your water level to be at. I didn't think about it at first, so you'll see in the pictures that they're at the edge, I later had to adjust this, but there's a picture of that, too. Make sure your water level is high enough that the bottom of your cups will be submerged.

My pump came with a removable attachment for the tubing, so I wrapped one side of it with Teflon tape and used plumbing cement to attach it to a piece of tubing long enough to reach from the upper tube to the bottom of the reservoir. I then pushed the tube through an end cap's hole. Push another piece long enough to reach from the lower tube to the reservoir. Then attach two end caps via tubing long enough to fit on both pieces of PVC.

When I tested the system like this, it ran surprisingly well, with a just a few small leaks. Use the plumbing cement to seal around the outside of all the tubes. Plumbing cement isn't the most safe substance (toxicity wise), and even though it's probably OK, by just sealing the outside, it at least makes me feel better about. Luckily this stuff cures in two hours, so you can do another test run pretty quickly.

A lot of people recommend cleaning everything with a heavily diluted bleach solution to help ward off algae. I did this before I had drilled any holes. It was easy to fill the pipes and then shake them with the end caps on.

Step 5: Holes

Depending on your plants, the spacing of your holes will be different. I wanted to plant at least six plants, so my spacing worked out to be 8-9 inches between each hole. I would have spread them out farther if I could, but my PVC isn't long enough.

We have an adjustable door knob drill bit that drills holes up to 3" wide, so I cut a skewer to 3" and found where on my plastic cups they have that diameter. Hold it up to the PVC and see if it's deep enough. It was. Unfortunately, the only drill we have with a chuck that could fit that bit was a hand drill. At first I tried the "drill a whole every millimeter and cut it out" method...but I didn't have the patience. Instead, I used a 2.5" drill bit and sanded the rest down with my Dremel. If you have to use a Dremel on plastic, make sure to wear a mask in a well ventilated area and clean up all the dust afterward.

Rinse the dust off of the pipes.

Step 6: Assemble

Bring everything out to your final destination and set it up. Because mine is up against the screen of our porch, the lower side faces out, so everyone can get equal amounts of sunlight. Double check that the stands are all in the right orientation...i spent about 20 minutes trying to figure out why the water wouldn't run correctly.

I drilled three holes in the lid to my bucket, one for the intake tube, one for the output tube, and one for the power cord. It allows me to leave the lid on, and thus help prevent algae from growing.

Step 7: Cups

Drill plenty of holes in the bottom and edges of each plastic cup, for the roots.

Use the cups to measure out clay balls into a bucket of water. The water will wash off any dust that has accumulated on them.

Step 8: Planting

Carefully use a hose (I like the flat setting) to clean as much dirt as possible off the roots. Try not to mess them up...they don't like that so much. Once they're clean, surround them in the cups with clay balls. Use enough that they can support themselves and stand tall.

When you're arranging the plants in the system, keep in mind what kind of plant they are. Put taller plants in the back, so they don't block the sun. My plants that grow heavier veggies are on the lower section, so that I can build a table from the plywood and 2x4's to support their crops.

Step 9: Nutrients

Mix according to the label. Mine required 20mL per 4L. Because I don't have any way of measuring mL, I converted it to about 4 tsp per 4L and mixed it in a 2L soda bottle. That was a pain. Next time I make it to the hydroponics store, I'm definitely buying a syringe.

  • Nutrient solutions come in all sorts of varieties. I bought a general purpose "grow" solution that also has a "bloom" counterpart for when the plant begins to...bloom.

Step 10: Maitenance

The nutrients have to be changed periodically, and it's hard to tell when it needs to be done. People do it anywhere from once a week to once a month, and it depends on how much you mix at a time. recommends that you add fresh water as it's used by plants, because even though water is absorbed, nutrients still remain, and can get more concentrated. They said that once you've added half the amount that was originally in there, it's time to change. So with my 7L, once i've had to add 3.5L of additional fresh water, the nutrients will be mostly depleted.

Some people also monitor their ph levels. Pool stores generally will check it for free. I don't have a lot of information on the subject to offer, however.

Other than that, there isn't a lot that you have to do except care for the plants as you usually would.

Step 11: Resources

  • Instructables has a lot of great information on hydroponics
  • has a good FAQ
  • has a good explanation of some types of hydroponics
I hope this helps with designing your own system. Feel free to leave questions, comments, and most importantly, advice, below. Thanks!