After about a week it started to bubble properly and skim really well, but I did a water change again to test the chemical in the water conditioner theory and it has been confirmed. I'm going to switch to ro/di water for my next water change. They sent me a pump replacement, but I'm hesitant to put it on... Out of the box it was scuffed up and looked used. If it functions properly then it's fine, but I also want to wait until my water is clean of the water conditioner before I attach the replacement. I don't want the replacement to have the same problem because of the water. I'm thinking of switching pumps once I do the water change with ro/di water.
Is there any way to test the pumps to find out if one is better than the other?
I don't really trust the replacement they reluctantly sent me...