I am hoping to move into a new house soon. If all goes according to plan. Since I have both dogs and cats, as well as the finny friends, I am going to treat the house for fleas first. Don't want to chance it. This would be done well in advance of moving in. Most products that I have checked say to leave the house for 2 hours. Since we won't yet be moved in that won't be a problem. My question is even if we allow plenty of time, days or even weeks before moving the fish tanks do you think it will have adverse effect on the fish? I can't find anything that says it is toxic to fish. I have however found a few that say it is toxic to cats. Certainly staying away from those. Thanks for your help.