RSS Facebook Twitter YouTube





Please consider registering

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —

— Match —

— Forum Options —


Minimum search word length is 4 characters - maximum search word length is 84 characters

sp_Feed Topic RSS sp_TopicIcon
Oscar is not eating, breathing heavy, listless...Please Help!
April 4, 2013
9:58 pm
New Member
Forum Posts: 7
Member Since:
July 26, 2011
sp_UserOfflineSmall Offline

Hello everyone,

I thought my Oscar was just being temperamental (as usual), however, she/he(?) has stopped eating, is breathing (fairly) heavily and generally looks inattentive. I'm very worried since he is usually ravenous for food, breathes normally through the gills and is very attentive (especially for food)! also, I just saw him resting on the gravel, on the ventral/'stomach' side. 


Here are some of the particulars about my tank:

75Gal Tank, 2 Aquaclear 110 filters (one filter that runs 24/7/365, and the other filter that runs approx 8 to 10 hrs/day).


Contents of tank:

2 Oscars - one approx 11inches (the one with the problem) and one approx 9inches

1 Jack Dempsey approx 5 1/2inches

1 Geophagus approx 6inches

1 Convict approx 4inches


Water change of 25% once a week (including gravel cleaning and inside glass cleaing)

Clean both filter approx once every 2months

sponge, carbon filter media replaced approx once every 4 months


Please help me!!!  noexpression.gif


Thanks, Rob

April 5, 2013
12:43 am
Bellingham, Washington U.S.A.
Community Helper
Forum Posts: 1258
Member Since:
March 14, 2009
sp_UserOfflineSmall Offline

Hi Rob,

Sorry about your fish. I'm not an Oscar keeper but a few things that jump out at me.

Are you testing your water parameters? The usual Ph/ammonia/nitrite/nitrate.

It seems like with that fish load 25% weekly may not be enough.

As for your filters why do you turn the one off? By doing this you'll be killing off the bacteria that process the massive waste those large fish produce. Aquaclear sponges last forever so no need to replace those and I'd definitely replace the carbon with biomedia, as much as you can fit in the filter box.

That sounds like a big old Oscar and maybe it's just his time? Best of luck!


Edit: Depending on what all you have in that filter, and how long the carbon has been in, the carbon may have gone biological and may be housing most of your bacteria. So if you do replace it, it would probably be better to do it in increments rather than all at once.

April 5, 2013
2:02 am
Community Helper
Forum Posts: 1134
Member Since:
January 11, 2011
sp_UserOfflineSmall Offline

Appending to what Plaamoo said I wonder about
"Clean both filter approx once every 2months"
Actually when there are two filters, they should be cleaned one at a time. With large bioload, cleaning both may kill the biocycle. And if you want to use carbon (not saying you should!), you should replace it more often, like every month, because it loses its activity quickly.

April 5, 2013
10:41 am
Brunswick / Germany
Forum Posts: 349
Member Since:
May 2, 2012
sp_UserOfflineSmall Offline

Hi Rob,

unfortunately I can't tell you either what's wrong with your Oscar and since that is your actual question, I hope you don't mind too much if I elaborate on the point, both Jim and Mike have made.

The only filters, which should or rather can be run "part time" are chemical filters and mechanical filters such as uv filters for instance. As Jim has pointed out already, whatever amount of bacteria can settle in the filter media during the 8 - 10 hours operating time will be dead long before the "resting time" is over. Thus, you initiate a micro cycle every time you switch that filter on again alas with no benefit whatsoever to your tank and fishes. In addition, when you switch off, you reduce water agitation = gas exchange = oxygenation.

Carbon as a filter medium ONLY makes sense if you have to eliminate chemicals and/or heavy metals in your tank water. But if you had a problem with that, be assured that the tiny carbon pads, which fit your filter, would be entirely insufficient. If you feel that your tap water needs that kind of filtering, you should do that before you do your water changes.

From my experience, a biological filter should ONLY be cleaned once its performance decreases noticeably. I know this sounds contradictory to what is commonly taught, but the "scheduled cleaning intervals" are actually aimed towards the pre filter parts and (useless) carbon pads in the filters. If you eliminate them entirely, your filter will "tell" you when it needs cleaning.

It is a good thing to have 2 filters running but only if 1. they both run 24/7 and 2. if you, as Mike has pointed out, clean them alternately. This way there's always one filter doing the job, whilest the other can recover from the violation of it's biological balance.

Now, if your Oscar is suffering from any ailment other than age, it most likely is caused by the tank water and your "unusual" filtration schedule could be the cause.




If you must insist on living in a box ...... at least do your thinking outside.
May 16, 2013
7:39 pm
Garden Grove, CA, USA
Forum Posts: 10
Member Since:
April 27, 2013
sp_UserOfflineSmall Offline

Hi Rob!

I am feeling so sad for your fish.

You mentioned that your Oscar is breathing heavily. Heavy breathing could be a case of lack of oxygen in the water, have you made any adjustments to the pipe that returns water back into the tank? For a good supply of oxygen plenty of surface agitation is required.

Also you need to check and clean your filters.

Please let us know how is your Oscar now.

Alan Young

May 17, 2013
9:46 am
Málaga, Spain
Forum Posts: 8239
Member Since:
June 13, 2011
sp_UserOfflineSmall Offline

Dear Alan Young. I fear this is not the site for you and will be forced to take action should you continue to post nonsense on these boards. I also notice a link to a commercial site in your signature which is against our rules - this will now be removed.

Cake or death?
May 19, 2013
7:12 pm
New Member
Forum Posts: 3
Member Since:
May 14, 2013
sp_UserOfflineSmall Offline

Hi Rob, is your fish doing any better now? I had a fish, gasping- went off food and it was increased nitrates. I hope your Oscar is doing better.

Forum Timezone: Europe/Paris

Most Users Ever Online: 246

Currently Online:
1 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Devices in use: Desktop (1)

Top Posters:

Stefan: 1567

Plaamoo: 1258

mikev: 1134

Malti: 1099

Mark Duffill: 1012

Member Stats:

Guest Posters: 0

Members: 30837

Moderators: 0

Admins: 2

Forum Stats:

Groups: 4

Forums: 10

Topics: 4604

Posts: 36651

Newest Members: TheBigGuppy, moanatat, strawcan, LiSmi, JoshLangston

Administrators: dunc: 1323, Matt: 8239