New Tank Dead Fish, Help

[Taz and Elmo]

We are hoping that someone can help. We have had several tanks in the past. from 29 gal to 175 gal. All freash water. Never had a problem with start up or up keep. We recently purchased a 36 gal bow front. Looks great, have put in the tap water conditioner, checked the ph 7.0 and temp 78 deg. We put in 6 stripped dano's and 6 black skirted to start. after floating them and mixing the water a little at a time. Always used them before. With in hours they were dead. Took a water sample to Petsmart and they tested it and it was good. Gave us new fish and they lasted about 12 hours. We are at wits end. We don't want to torture anymore fish so does anyone have any ideas?????????????

[Cornstar]

Where did you get the tank? It could be possible that there are chemical such as soap or detergent that may kill fish quickly.

Also, cycling a tank is important before putting fish in.

[Jill]

I agree about the possibility of detergent. And fish-in cycling is fine if done properly (LOTS of testing and water changes).

[Taz and Elmo]

tank was brand new in the box. I'll drain it and stating over. Hope that helps.

[Mumma.of.two]

Welcome!
Sorry or your losses. My guess is something must have made its way into the tank. Ammonia wouldn't have built up that fast. So that's not the problem. I would rinse everything in HOT water and replace filter media before starting again. Make sure you add dechlorinator. What one are you using?

Do you own a test kit? If not, it would be a good idea to get your own liquid one.
Here are the fish in cycle guides. They give tips on how to keep your fish safe (by doing water changes) during the cycle.
FISH IN
http://www.aquariumadvice.com/articl...now/Page2.html

http://www.aquariumadvice.com/forums...de-176446.html

BEGINNERS GUIDE
http://www.aquariumadvice.com/articl...ium/Page1.html

[redsea]

Welcome to Aquarium Advice, sorry about your losses.