Well, what I did to cycle my fish was I went to the lake and caught about 10 small brim. Put them in my tank-were there for two days. Eventually I felt sorry for them and today I put them back into the lake. My question is- can I do a partial water change, then perhaps today go get some zebra danios to continue the process?

how big of a tank? also Danios are very hardy to the chemistry. Do you have a test kit to watch your levels?

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55 gallon.... Getting a master test kit tommorow.

try to avoid impulse actions and be patient. the cycle will take care of itself if you start slowly. If you add the danios, just let them have the tank to themselves for at least a week if not two. test the water every few days and wait until nitrite reads zero before adding more fish... then proceed slowly with only a few fish at a time and being very religious about weekly 10% - 20% water changes.

this way can be boring because of all the waiting and the empty looking aquarium, but you will be happier long term with a healthy and stable aquarium.





also, as a side note;
once fish are removed from the wild and introduced into an aquarium, fish should never be re-introduced into the wild. This prevents any disease or parasites from being introduced into your local fish population. in your case the fish were in a new tank and exposed to no other fish, so no big deal, but it is a good practice to re-home or euthanize any unwanted native (or exotics for that matter) fish instead of releasing into local waters.

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Gold Coast Aquarium Society South Florida
www.goldcoastaquarium.org