So I've finally decided on getting my cousin a fancy goldfish for her birthday. I figure since I'm going to be the one caring for and living with the fish, I should take advantage of having the coldwater setup and get my weather loaches! I'm not sure what size tank I'll need for this, or what kind/how much filtration. I think with such big fish in there I'm going to need to at least double the filtration. Ideally I could get a 40 gallon and have 3 loaches in addition to the goldfish... but I live on a second floor (third if you count the basement) and I'm not sure if that would be too heavy. So the second option would be a 30g long with 2 loaches and the goldfish. I don't like this idea as much, I'd prefer if my loaches were always in a group of at least 3... What do you guys think?