all my fish died

Question
Hi, I just moved from one house to another. I have a 90 gallon tank with about 12 fish in it. To move i took out most of the gravel on the bottom and sucked out about 80% of the water. Once i got it to the new place i filled the tank back up. When i went to bed last night the tank was clear and everything was fine. I woke up this morning and you couldnt see in the tank and all but my parrot fish was dead. What do you think happened. What should i do before getting new fish. thanks for any help you can give.

Answer
Well, it could be a number of things which caused it. One thing which if it did not cause it had a big part in it would be the stress. While you did what you could, sometimes fish react in crazy ways and cant handle what we think they can. I assume you remembered to de-clorinate. I assume you did but its a valid question and even I have to remind myself and have come super close to messing that one easy step up several times. One other thing, if the gravel was exceptionally dirty and had alot of excess waste in it, when you syphoned it it could have released toxic waste and that could have contributed. One final thought would be that the fresh water, not being cycled, was extra stressful for the fish. Honestly, considering it happened after such a move I trust that it was simply stress. However, to be sure, I would wait a week to make sure your parrot does not die. If he develops any signs or disease or parasites you will have to treat him and wait even longer. But assuming everything is good for a week, I would believe it is safe to begin re-building your tank. Let me know if you have more information as to the possible deaths of if you just have more questions. I hope I have helped you!