platty

Question
I just started my tank up on Thursday 29 January. I have mollies, swordtails, cories, angels and platties.  On Saturday my mail sword died, but he never fed.  My smallest platty died, then I lost male molly, had all his tail nipped of, now I have lost another platty with its tail half gone.  One of my patties is pregnant and is very rough and pushy, is it because she is pregnant and could it be her doing the damage

Answer
Hi Shonah;

Oh, my. I think you've been given some very bad advice in stocking your tank so soon. I would say the deaths are probably due to "New Tank Syndrome". Waste toxins are poisoning them because the system hasn't had time to biologically balance yet. That process takes at least 4 weeks, usually more like 6 weeks at least. You didn't mention what size tank you have or how many fish you actually have in there. Based on what you did tell me your tank would have to be at least 70 gallons in order for that many fish to be safe in a new tank. Get the water tested for the ammonia, nitrite and nitrate levels. The results will tell you how serious it is so far. If you could tell me more about your system it would help me give you more detailed advice. Here is a link to my page on new tanks to help you understand more about what's going on in there;

http://www.xanga.com/Expert_Fish_Help  

Your best bet would really be to take most or all of the fish back to the fish store and leave the tank empty for as long as it takes for the toxin levels to drop and the bio-system to stabilize. You could then add a fish a week until it is at the safe population you want. Slow additions helps the bio-system have time to compensate for each new fish. I don't know if it's even possible to save the rest of the fish at this point. For now, replace 25% of the water every day until you can decide for sure what to do. The toxin levels will continue to rise to lethal levels even as you make partial water changes if all those guys are left in there though.

At Your Service;
Chris Robbins