ammonia in tank

sally · 04-23-2002, 03:54 PM

I have a 30 gallon breeder tank with about 40 two month old bangaii cardinals. I have been feeding the tank heavily since the fish are babies. On Monday I noticed an ammnia reading on the tank. I used a Fast Test kit and it was at 0.4. I did a 20% water change yesterday and a 10% water change today. How much (%) of a water change can I do at one time? Could I do a 50% water change or would this shock the fish? I plan on doing daily water changes till the ammonia is gone. I have also cut back on the feedings. I do have a skimmer on the tank but not a great one (big mombasa). The fish seem to be doing fine. I've never had this problem before so I am very concerned about the welfare of the fish. Thanks in advance.

JMOR · 04-23-2002, 04:06 PM

Im not a big fan of 50% water changes at one time unless it is a big time emergency. I would do 20-25% water changes for the next couple of days until the ammonia gets down ..... I would also run some carbon if you are not already.

Rick O · 04-24-2002, 05:40 AM

Hi Sally.

Sorry I missed this yesterday.

What effect did the two water changes make on the ammonia? If they dropped the ammonia significantly then I would do daily 20% water changes. If the fish aren't showing any signs of stress then I would be reluctant to do a 50% water change at one time.

Rick O · 04-24-2002, 05:42 AM

One more thing. I can't remember if you had any hermit crabs in there. I would put a few in to take care of any of the fish that might die and go un-noticed.