dmm28

I'm thinking of going the DIY Co2 route. I've read quite a lot about the whole subject but want to make sure I'm understanding everything right fist.

So basically you need to have a couple 2 liter bottles to hold your yeast, water, and sugar, 1 smaller bottle as a gas collector, a few check valves, some tubing,and a diffuser of some sort.

Now here's where i'm having some trouble. I've seen people talk about drop checkers and bubble counters. Obviously this is how you measure how much C02 is going into the tank right? My question is how do you make either or both of these items yourself, and what are the proper levels you are looking for? Also with a DIY setup how do you control how much Co2 is going into the tank?

Jess

As I understand it the DIY Co2 route is best for smaller tanks.
What size tank are you thinking of using one on?

dmm28

75 gallon. I'm looking into the high end setup as well today.

dmm28

Well I just found out that a basic Co2 set up is going to cost me just over $300 Canadian That's a ton of money! Especially right after x-mas.

soldieroffortune1974

The CO2 isn't just for small aquariums.It really depends on the amount and type of plants in the set up.

So basically you need to have a couple 2 liter bottles to hold your yeast, water, and sugar, 1 smaller bottle as a gas collector, a few check valves, some tubing,and a diffuser of some sort

The smaller bottle is more of an ovrflow prevention. If your mixture overflows from the bottle(s) containing the mixture,it will collect in the smaller (empty) container,instead of getting into the aquarium.

The best type of diffuser to use is ceramic or glass type diffusers. The stone doesn't hold togetrher very well and clogs easy. The best type will produce as fine of bubbles as you can get.The more,smaller bubbles the better.A power head of some sort or reactor will help in that.

Now here's where i'm having some trouble. I've seen people talk about drop checkers and bubble counters. Obviously this is how you measure how much C02 is going into the tank right? My question is how do you make either or both of these items yourself, and what are the proper levels you are looking for? Also with a DIY setup how do you control how much Co2 is going into the tank?

I don't use drop checkers or bubble counters. The best indicator of how much CO2 is in your water is pH and KH/GH,but if you're not into the technical aspects (fairly involved explanation) You could benefit from a bubble counter.

It's not a good idea to control the CO2 flow on a DIY set-up,restricting the flow will cause your bottles to become pressurised and KA-BOOM,after pressure builds up,the bottles WILL explode. The best way to control the amount of CO2 going into the aquarium is controlling how long the bubbles remain in the water.The longer they are in the water,the more CO2 is dissolved,less time in water,the less amount that is dissolved.

pepetj

I keep DIY CO2 systems running in two planted tanks.

Angelfish Tank, 29gbow and Rainbowfish tank 45g long +10g sump.

For a 75gal tank long, I figure this is what you should do:
Two separate units to feed at opposite ends built on:
three 2L CO2 generator + one 20oz Gas separator + 1 DIY-tiny-efficient CO2 reactor each if the DKH in the tank before injecting CO2 is at or above 7. With lower dKH, say 5 or 4 I would go with two 2L instead.

Important issues commonly overlooked:
1) Sterilize all your bottles with hot water before you add any recipe. I just heat water in the microwave oven and stir it inside and around my bottles, shake a bit, and then add cold water. This way I use two different strategies to kill bacteria that would compete with the yeast and make the CO2 recipe useless.
2) Add 1/4 teaspoon of baking soda to raise your recipe pH, yeast will work a lot better that way.
3) jump-start your mixture: I add the diluted two cups of sugar to the sterilized bottle first to every bottle I am preparing, then one by one I do the following: mix hot and cold water until I get tepid water being careful of not going over 100F. Add the yeast and the baking soda, mix well by shaking with a small teaspoon, and add to the 2L bottles.
4) Some air is needed in the bottle, otherwise it could explode and get your room all dirty. As I use coke bottles, then I fill up to the upper curve.
5) Silicon is useless to seal most soda caps. I aim at mechanical sealing by drilling the hole carefully and if needed I use a short air-hose section or teflon tape to achieve a tight sealing. When unscrewing the cap I rotate the bottle not the cap!

I set both units with fish living in the tanks. I was very careful to prevent a pH crash.

I built my modified versions of CO2 drop checkers that work wonderfully. You can see it right in this DIY sub-forum.
DIY CO2 monitor

Pepe
Santo Domingo