Goldfish tank questions

[mtwang]

I'm fairly new to having fish and have a 90 gal tank with 5 either commet or common goldfish (about 2-3 inches in length and 2 years old) and 2 snails.

I'm not sure how often I should be doing water changes, as the tank is bigger than there would usually be for goldfish fish that size from what I've heard.

We currently have a large filter set up on it and a oxygen thing that suits 60 gals (I figured that while the fish are smaller that maybe we could get away with a 60 gal oxygen-ifyer thing).

Does anyone have any opinions on how often I should be doing 25% water changes, and if I should be doing other cleaning things? And if the oxygen thing is probably good for now while the fish are not full sized?

We also had a pleco in it that died, which I figured was maybe because the water was room temp and not heated. Does anyone have any opinions on whether there is a catfish that would do well in this setup and whether we could get two rather than one? I got one since I worried that the pleco's would fight or be too big once both they and the goldfish were bigger.

[King Fisher]

Actually, 90 gallons is cramped for even two common or comet goldfish once full grown let alone 5 of them. Most people put that many in small ponds as they grow over a foot long.

I'd do weekly 50% water changes. The best way to gauge when you need to change your water is by testing your water every couple days to see what it's doing.

What is this oxygen thingy? Is it an air pump with airstones?

I would not add anymore fish to your tank. Plecos are pretty tough and can stand cool water temps so something else was going on. I think if you add anymore fish your gonna have a big problem on your hands down the road.

[BBradbury]

Originally Posted by mtwang

I'm fairly new to having fish and have a 90 gal tank with 5 either commet or common goldfish (about 2-3 inches in length and 2 years old) and 2 snails.

I'm not sure how often I should be doing water changes, as the tank is bigger than there would usually be for goldfish fish that size from what I've heard.

We currently have a large filter set up on it and a oxygen thing that suits 60 gals (I figured that while the fish are smaller that maybe we could get away with a 60 gal oxygen-ifyer thing).

Does anyone have any opinions on how often I should be doing 25% water changes, and if I should be doing other cleaning things? And if the oxygen thing is probably good for now while the fish are not full sized?

We also had a pleco in it that died, which I figured was maybe because the water was room temp and not heated. Does anyone have any opinions on whether there is a catfish that would do well in this setup and whether we could get two rather than one? I got one since I worried that the pleco's would fight or be too big once both they and the goldfish were bigger.

Hello mt...

Goldfish aren't tropical fish, so they need cool water around 68 degrees. Their tank doesn't need a heater. Plecos are tropical and need warmer water. If you want to put some other fish in with the Goldfish, then Rosy Reds or White Clouds will work. They don't mind cool water. Your 90 gallon tank will be fine for your Goldfish for quite a while. They get quite large, but this takes years. You need to change out half the water weekly. Small water changes do little to maintain livable water conditions for fish in general. Goldfish are heavy waste producing fish and need larger, more frequent water changes.

B