My DIY Co2 starts reacting within 10 minutes.
First, try a plastic bottle instead of a glass jar.
Make sure your yeast is active. It must be kept refrigerated after opening, and should be replaced after 6 monthes or so.
Always let the yeast come to room temp(it is alive), so you don't kill it. To test to see if it is active, let a bit sit at room temp for 10 minutes, then drop it into some warm water(not hot). If it starts to foam in a few minutes(or hours in ron's case
),then it is active.
You should NOT be able to smell it if your bottle is sealed(I have 5 bottles under my tanks, and I do not smell it til I change it)
azn, the amount of Co2 must also depend on how many plants you have to use it. If your tank is not very stocked, go buy some and stick two bottles on. Like somonas said, if you have nice light, Co2 is a nice addition, but ferts are needed as well.
AN algae crew is vital for algae control. A bristle nose or rubber pleco is the best for the glass(blows away all my ottos), ottos for the leaves, along with some SAE for the plants.
I left my tank run for a few weeks without an algae crew...everything looked bad. Ran out today for some, now need to go find some SAE for the slight hair algae that cropped up.
Good luck.