I have a 36 gallon tank and I know I shouldn't have but I got some clown loaches. Well its been a couple years now and their getting big. I do weekly water changes but the PH is low and the nitrate isn't good. I may be wrong but I'm guessing thats from the tank being overcrowded from the clown loaches getting big. So a fish store near me said they would take the clowns (they have a big like 300 gallon tank with big clown loaches in it that sell for a pretty penny) Thats good but I know clown loaches are sensitive to water quality and I worry the clowns will die if their moved to the tank with (hopefully) better PH and nitrate levels which would be different than their used too. I'm guessing they would be fine if they sat in their bag floating in the water for a while but advice would be greatly appreciated.

They will be fine if properly acclimatized. Clowns do better in larger tanks for sure. I have 2 in my 90gal

Tank Ph can change as the tank get dirtier. Usually the PH drops.

Where i buy my fish use town water (high PH), i use tank water (low PH). When i buy new fish, i float the bag for 10min, then start to add the tank water into the bag, 10min later i release the fish into the tank. Some i get them home and just drop in. Havent lost anything yet *L* But i will say try to do my former route rather than dropping them in, as it may not work for you