I had been away for a few days and noticed that my Oscar was behaving a bit unusual. i checked the tank and noticed that the water was quite warm, that was when i realized the heaters th/stat had failed, causing the heater to stay on. Anyway, I removed the heater and replaced with a new one. Since then my O has been very lethargic and has not eaten for approx 3 weeks. I thought he was dead a few days ago, but he has picked up a bit from then but still refuses to eat. I checked the water and ph etc is all normal.
I was reading elsewhere that too warm water causes nerve and organ damage.
Now to compound my dilemma I am leaving on a 2 week vacation on Friday, we do have a friend staying in the house but I can't really expect here to try save my fish. He is difficult to feed even when all is normal as he is blind in one eye so he quite often cannot find the food.
Any thoughts on the warm water? could I have possibly "cooked" my O?

Well you are correct,any creature can only withstand a certain temperature before it starts affecting them, fish are no exception. obviously we really can't say whether or not your fish has been seriously affected by this unfortunate HICK-UP with your heater. The only thing you can do is keep the water at an acceptable level and hope for the best. How hot did the water get?

As for the Oscar and not eating, if I had a pound for every time somebody asked a question about this, I would be quite a rich person. Oscars can stop eating for many reasons, sometimes we just don't know why they do it.

If you're going on a holiday that you'll just have to trust the person to look after the fish. Can't really say any more than that I'm afraid

I did not think to check the temp when it was hot, but it was very warm, if it was a bath tub it would have been a very nice warm bath, (except for the fish that was in it)

I have to say, I have had this happen before. Never with an Oscar but I did with Goldfish and some tropical fish as well... The water in my tank got to 94 degrees Fahrenheit. I quickly, turned the light off.. And changed about 30% of the water. I didn't want to send them in to shock but it was bad enough that 8 fish in the tank were already cooked.. I waited several more hours and changed another 30% of the water. I then left it over night. In the morning all the fish seemed slow but the tank was back to 76 degrees. They did recover and are still swimming..

Now I know O's and goldfish are different but I figure that goldfish are cold water fish and O's are warm, if you brought the temp down, just give it some time.

Okay, even more difficult to say whether there is a serious problem if you don't actually know what the temperature was.

What was the heater temperature set on?

Does your fish look like it's struggling to breathe?

This is quite a coincidence. Just today we reopened a 29g tank to eleviate my bio-load on my 75 that now houses 3 near adult O's. I was not intending to have 3, but I felt sorry for an O at the pet shop that was being housed in a 30g with a divider and he only had half the 30 to swim in, But anyway, I put the two fully mature africans in the 29 along with a goldfish that we got attached to. (was a feeder that survived about a year now and managed not to be eaten) I got a heater out of my box of fish goodies and put it in the 29g. I guess I neglected to set the thermostat in my haste and about 30 minutes ago looked at the temp and it was about 81 degrees F. I corrected the problem and I think all will be fine.

Sam, 80 t0 81 deg F is normal during medicating against ICK,
thus, it won't hurt the fish except the depletion of oxygen.

ausie01, since you failed to check up what temp your tank
attain, we can not ascertain if your fishes were damage.
cross your finger they don't suffer that much. as to your
scheduled leaving the tank again, i suggest you check if is
cutting off once the thermostat setting was reached.

PAUL wrote:


Yeah, I knew it wasn't at a critical temp yet, I was just thankfull I caught it.
I do know that a temp change alone will sometimes rid your tank of ick by speeding up their life cycle. I have had tanks get in the low to mid 80's not even running a heater when I was young into the hobby, Couldn't afford A/C and had tank in front of the window. But now that I am old as dirt, I have learned ways to keep temps at a reasonable high. I have had aquariums pretty much all my life. But I never fail to learn new things. I have found this site to be a real asset to my inquisitive mind. I learn something almost daily here. Thanks to all of you.

hey Sam, you can also keep that green algae under check if you increase
the lateral surface or volume of your bio media. one of my tanks
gets plenty of sunlight everyday and had hit by green algae only once.
i was able to maintain crystal clear water tank with plenty of sunlight.

PAUL wrote:


right now my tank is 78 - 80 degrees. It feels cool to the touch in comparison to what it was. My guess is it was 90deg + when I turned the old heater off.

I just got the 4 stage canister that Nicki recomended. It has cermaic rings, and bio-balls, you think when the bacteria estabishes in it, that might help my problem? Actually I think that green algae is not harmfull to the fish, but it is not very appealing looking at.

Trader Sam wrote:

yes, it may cover your algae concern. can you check what is the flow rate? as compare to your tank size.


no, they are not harmful but an eyesore if you can not see your fishes very well. and i just scrub the glass wall everyday to keep them away from the glass