hairy goldfish

Question
Hi-I have a 29 gallon tank that I have had set up for about a month and a half now and I have lost 5 fish just today!!  The remaining fish (about 8) look 'hairy'.  I consulted my local pet store and was advised to change 50% of their water and vaccum the rocks really well and then treat the tap water and re-fill the tank.  The remaining fish are still hanging out in the bottom corners of the tank.  I also bought an amonia monitor to be sure that the water was staying clean.  It is cloudy already again.  I am at a loss and I am afraid that I am going to loose the remaining fish and have to start all over again.  I do have a heater in the tank which seems to keep the h20 around 74, and it hasn't been a problem.  Are the remaining fish going to be lost and what else can I try to do to save them?  Thank you for your time!!

Answer
Hi Heather;

Oh my. I'm so sorry you and your fish have been going through this. Somewhere you were given some bad advice on stocking your new aquarium. You just have WAY too many goldfish in there. Especially for such a new tank.

When a new tank is set up it's basically a pretty clean environment. That's actually bad news for your new fish though. They need beneficial bacteria colonies in the tank to control their waste but they take several weeks to grow mature enough to do that. Until it does, waste toxins rise. When the fish are added and waste is being introduced to the system, the beneficial bacteria colonies begin to grow on tank surfaces, decorations and in your filter. When a new tank is so overstocked it often stays cloudy because the beneficial bacteria just can't find enough places to colonize enough for the excess waste to be processed in the system. If the overcrowding isn't corrected the tank may always remain cloudy.

Goldfish are very messy guys even while small and only 3 can live in a 29 gallon at the most. The "hairyness" may be a reaction by their slime coat to the stress, or a bacterial infection that they were sensitive to because of the stress they have been under. Your tank may still be trying to break in and waste toxins (ammonia and nitrite) have burned and poisoned them, weakening them. The cloudy water is a very common symptom of the break-in process, also known as "new tank syndrome". It can take up to 8 weeks to complete. Check the levels of nitrite (not nitrate, it's different) and see if it's elevated. If so, keep up with water changes to help get them low enough for the fish to tolerate them.

I really don't know if they can be saved but making a 50% water change every day or two is a good idea for right now. If they do have a bacterial infection and you add medication to the tank it could kill off some of the beneficial bacteria. You may have to medicate anyway and just deal with the effect on the bio-system by making more water changes.

It's important to be very light on feeding the fish right now too. Feed only a very tiny amount every day or every other day. While they are sick they really can't digest very well anyway and it only adds to the waste load that the system is already having a hard time coping with.

Don't vacuum the gravel any more. If you think it's needed due to a lot of waste, do it very lightly. The tank is too new and vacuuming will kill off some of the beneficial bacteria that is growing in there. The disruption will add to the cloudiness and instability of your tank. New tanks should not be vacuumed until they are through the break-in and fully stable. Don't change any filter pads (if your filter has them). If they get plugged, rinse out any crud very gently in a container of tank water. The beneficial bacteria clings to the filter pads and on gravel and decorations under water. It needs to be preserved and treated as a living organism, because that's what it is. Gently rinsing waste out of the filter pads keeps them working but leaves most of the beneficial bacteria intact. If you can avoid touching them at all, it's best but the filter has to keep working so sometimes it's necessary.

I hope they get better soon. Let me know how it's going...

At Your Service;
Chris Robbins