LondonDragon said:With DIY you can't, just let it all go into the tank 24/7, that's why you need to start with one bottle and measure it with a drop checker and then if you need to had the second bottle, the air pump during lights out will give the fish a break and prevent them being poisoned.Richard2510 said:Just had a quick look at these. I think I'll get a couple. How do you control the flow rate?
EDIT: Corrected punctuation as made aware by Mark, cheers
Right, I'm with you. I'm gonna order one, get it up and running (with an air pump running on a timmer set to the opposite of the light) then keep an eye on it using the drop checker and then see if I need a 2nd one.