What is hydroponics?

Hydroponics is the growing of plants without any soil. Plants require three things to survive – Light, Oxygen and Nutrients. Since soil is the normal source of nutrients for plants, when removed we need to replace it with something else. This is usually done by adding nutrients to the plants water source.

What do I need for hydroponics?

There are many different systems you can buy or build for hydroponics. Unfortunately,  as with most things in the Philippines, your choices will be limited.. so be prepared to go the DIY route.

The systems generally all work along the same principles. You have your seed or plant which is held in place by an inert growth medium (e.g Rock Wool). The usual methods of supplying the plant with nutrients when growing hydroponically are:

1) Have the roots sitting in a mix of water/nutrients
2) Spray the roots with a water/nutrient mix
3) Drip feed a mix of water/nutrients

Some people take this a step further and use a cheap air pump and air stone to aerate the water which provides more oxygen to the roots and further helps the plants growth.

What exactly is an Inert growth medium?

Since we’re growing without soil, we still need something to hold the seed or plant while its growing. The medium is inert because it adds no nutritional value to the plant, it’s used only to support/hold the plant in place.

What growth medium you use will depend on the system you use and your own personal preferences. The most popular options are:

* Perlite – Volacnic rocks that are transformed into light pebbles through a heating process. Has the benefit of holding a lot of air which can be useful if you’re not using a air pump for additional aeration.

* Rock Wool – A fibrous material created from molten mineral substances. Drains well

* Clay pellets – Baked until they become porous and are able to hold/pass water. Roots can grow into these pellets.

What kind of systems are available or can be built?

Hydroponic Bottle Bubbler System

Although this is one of the simplest designs ever, it’s actually one of my favourites and most successful.

Parts list:

1 x 1.5 litre bottle (size doesn’t matter too much. Minimum of 1 litre)

1 x air pump+ 1 x small airstone + air tube

1 x plastic poly pot (or if you really want to go DIY then use a mold a plastic bag into the same kind of shape and poke holes into the bottom of it)

A handful of your favourite growth medium.

Some duct tape

Steps:

1) Cut the top (lid end) off your bottle. You should cut until the width of the bottle is about the same as your poly pot.

2) Run air tube from the air pump to an air stone. Place the air stone at the bottom of the bottle and use tape on the outside to hold the tubing to the bottle so the air stone wont move.

3) Insert your poly pot into the top of the bottle and hold it in place with tape.

4) Fill your poly pot with your favourite growth medium

5) Secure your seedling within the growth medium and pour your nutrient/water mix through the top of the bottle until its just up to the level of the holes in your poly pot.

6) Turn on your air pump and enjoy.

Finished Example:

Here you can see a cactus cutting in the hydroponic bubbler along with some small herbs beginning to grow.

Here you can see that I moved the cactus to its own hydroponic bubbler with the herbs beginning to grow to a reasonable size after about 6-7 days.

A bigger example of a bubbler system can be seen on my DIY hydroponics dwc setup page.

Hydroponic float system

This can be one of the simplest systems to build.

Steps:

1) Buy a hydroponics nutrient mix, a deep tray, a sheet of 1 inch thick polystyrene board, a pack of polystyrene cups and your preferred growth medium

2) Cut the polystyrene board into a square or rectangle shape which fits inside the dish with a 1cm space at each edge.

3) Cut circle holes in the polystyrene board for the cups to slide into. You want the cups to stick 1/2 – 1 inch out of the bottom

4) Make a 1x1cm hole at the bottom of each cup on either side. Fill your cups with the growth medium

5) Fill the tray with your mix of water/nutrients and place the polystyrene board inside the tray. It should float and the growth medium should start to absorb the mix.
6) Insert one seedling securely between the growth medium in each cup

Finished Example:

In this picture you can see that I'm using SNAP nutrients and polystyrene plates. My growth media is basic Rock Wool cubes.

In this picture you can see the plates are floating in the nutrient mix and the Rock Wool cubes are soaking it up. If you find that your cups are holding too much water then raise them up so they're not sitting so far down into the water and add more grow material. You do not want to drown your plants.

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Hydroponic DWC System

For the full build instructions, see the DWC hydroponic page.

Squash and basil growing in DWC hydroponics box

Roots of Squash in DWC/bubbler box.

If you’re looking for something smaller, or want more info about what hydroponics is and how it works then check out my hydroponics in the Philippines page.

	I bought a semi-transparent box from Shopwise for about 450PHP. Sprayed it blue to keep light out (light kills plant roots!).
	Then I drilled three holes. One for the temperature sensor and two for air tubes. After drilling the area was sanded and ready for a respray.
	Using a hot glue gun, I fixed two air stones in place.
	I ran the air tubes from the air pump to the air stones. I also used hot glue to stick the temperature sensor inside the box. Although the tube is a tight fit with the holes and the water should never go that high, I used hot glue around the holes to create a water tight seal.
	The next step was to cut holes into the lid for our plant pots. Unfortunately I didn’t have any tools at hand to do this (the plastic was too thick for a Stanley knife). I ended up heating a knife over and over and using that to melt/cut the plastic.
	The next step was to fit the plant pots into the holes. I’m using thin plastic poly pots. Fitted to the lid using duct tape. Eventually I’ll replace with strong plastic square pots.
	In this picture you can see the air pump running, making bubbles and the temperature reader attached to the outside.
	This is the final setup with lid connected. I’ve made temporary lids for 3 of the holes since I only want to grow three plants right now.
	Basil and squash growing in the hydroponic DWC construction. Using SNAP hydroponic nutrients.