Help! Aquarium changed, fish died
Looking for some advice because I thought I did it right, went from a 10 gallon to 29 gallon tank, three types of tetra groups with 3 fish in each, and two Otto’s. I filled new tank with tap water (I’m on well) as well as about two gallons from my 10 gallon tank, the same temp as other tank, 78 degrees, added 15ml water conditioner, swapped plants over, along with other random caves/ artificial log. Switched old filter from tank hung sump into the new sump. I then let it run for an hour, placed fish in a bucket of old tank water and slow added a cup of new water three times over 20 minutes, then netted them into new tank. This was 5pm yesterday, this morning I have lost 7 of the 11 fish, and water testing isn’t showing ammonia or nitrites. I did have a ton of bubbles everywhere after filling the tank, could it have off gassed into water or something hurting them?