quick DIY C02 question.
 

ive read all of the articles and understand makind C02 and stuff, but i heard it has to be diffused. since i dont have a canister filter (which is involved in most diffusing) i was wanting to use the air stone method but i was wondering if thats all you had to do, just hook up the line to an air stone and wait.

thats what i did. is this saltwater or freshwater. Because i did it in a freshwater.

its freshwater, did you just put an airstone or did you put the aristone under a filter or what?? oh and also can you have too much c02 in an aquarium? like enough to harm fishes? just wondering