I have had the idea of using co2 for some time now, the thought of those tiny little bubbles shooting up through the water to breathe ( literally ) new life into my aquatic plants was exciting. I like most people scoured the internet for a low cost solution which to my surprise worked. I found a DIY setup which supposedly released a steady amount of co2 into the tank.

the setup was easy and consisted of two large fizzy drink bottles some hose and an air stone I had, the theory was to mix yeast with sugar water with dissolved gelatine, what then would happen is the yeast would start to convert the sugar into alcohol the byproduct of which was good old co2, this was in the first bottle the second contained water these were linked with small plastic tubing with the co2 rising through the tube then cleaned in the second bottle then push its way through another tube into the aquarium, easy right? WRONG!!

for a start there was no regulator, now I’m no genius but if I remember rightly from my school days plants did not photosynthesise co2 into oxygen at night and with there being no on/off this would pump co2 into the tank 24 hours a day which could potentially kill my fish.

now as a cheap option this can be done you could buy a cheap regulator valve that would flow the co2 into the air at night saving your fish and you would still need to buy the tubing the bottle and the ingredients, this can get messy too if you don’t use enough gelatine you could potentially flood your aquarium with yeasty froth which will definitely kill your little friends.

eventually I found a better yet more expensive option on eBay, a 2l cylinder complete with bubble counter and stop valve, this stainless steel tank could be opened and filled with 200g of citric acid, 200g of baking soda then 300ml of water, then screw valve/top onto the container connect the tubing to an air stone or diffuser giving consistent co2 through the day and switched off though the night.

DID IT WORK.

Short answer yes it did, now depending on the size of your aquarium and the amount of plants inside depends on how much you have flowing through, I have tested this on my 60cm wide 120l aquarium which is heavily planted. I have the bubble counter set to 2 bubbles a second and this gives me roughly 4 to 5 weeks of constant co2, my plants have flourished they have grown not only in size but the colour difference is striking, also I have less algae growth to this due to the plants working overtime using all the spare nutrients in the water causing whatever algae left to starve.

In summary I advise save yourself some time and buy a £50 co2 kit on ebay they are easy to use, look great and really do improve plant growth inside your aquarium. below are a few tips you should consider using.

Try using an air stone instead of forking out lots of money on fancy diffusers, they do the same job at a fraction of the cost.

When its time to refill your tank do so on an evening once you’ve turned the lights off to the tank, this will give you time to refill the canister and by morning it will have settled with plenty of pressure ready to go.

Limit your co2 and light to your tank to 8 to 10 hours a day it will buy you more time before refill and allow the plants to rest before the next day.

Thanks for reading.