Fish Owners Are Out Of Town, Please Help!

[bugsingelyn]

My neighbors are out of town for a week and my job is to simply put one pinch of flake food in the tank, as per instructions they gave me. There are 4 or 5 fish in the large tank (maybe...18 inches across, hexagonal, and 30 inches tall), and one of the fish (not sure of the name, maybe you can help me?) is 6-8 inches long, gold, and has a puffy body. Yesterday, it looked completely normal, but today I went to feed them, and he looked very pale. I read somewhere that they lose color when they have a lack of light, and today was a cloudy day, could that be it? Should I turn the aquarium light on? It is not automatic. Am I feeding them too much? Too little? Is it something else? The other fish seem to be fine.
Thanks in advance.
EDIT: The furnace is broken, the temperature inside is 86 degrees. Is it too hot?

 

[Tolak]

A few questions, if you don't know the answers that is fine, almost to be expected in your situation.

First; can you take a picture or two of the tank, and post it or link to the pic? Second, fresh water or marine(salt water)? Third, live plants or not?

 

[deanT]

[quote
EDIT: The furnace is broken, the temperature inside is 86 degrees. Is it too hot?
[/quote]


yeah id say so

 

[Amunet]

Yeah, that water does seem to be a bit on the warm side.