CichlidFish.com - Fish That Think.

Hi,
I had 2 Oscars which are about 7-8 inches long which grew up together. About 2 weeks ago I bought another Oscar of a similar size and now one of the existing Oscars isn't eating properly.

The new oscar has been a bit aggressive but nothing too serious and this has calmed down a lot. The affected oscar isn't showing other signs of aggression such as split fins but did have signs of fungus which I treated with methyle blue and has now gone.

The other existing oscar is eating fine and has no obvious problems.

For the last 2 weeks or so the effected oscar has been eating very little. He does still seem interested in food but isn't eating it. I've tried getting different foods such as dried krill and frozen fish but he doesn't seem very interested even though the other 2 are loving it. He has also started to stay nearer the bottom of the tank than he used to but is still swimming up and down. Externally the fish still looks very healthy.

His usual diet was pellets with frozen foods such as beef heart about twice a week.

I've got a 100 gallon Jewel tank with a fluidized bed filter, the interal canister filter and an Eihem external filter.

I've tested for ammonia, nitrate and nitrite and they all look fine. The pH is about 7.4 - 7.6 (should this be a bit lower?).

I've not got any salt in the water - is this a good idea?

I usually change about 10% of the water a week and clean the filters at least every other week but have been cleaning the tank every fews days over the later week or too hoping it would help.

I'm not sure what else to say that might be useful to know but I'm running out of ideas on what to do - can anyone help please?


Stacy.

YOu are not changing out enough water..  The foods you are feeding is very messy.. With americans you need to clean the filter BOX out weekly..not just change out the filter media pad.. HOW much are you changing out??

here is some percentages for you:
100gal x .20% is 20 gal of water..
100gal x .25% is 25 gal of water.. EASY to do as 100 divides good into even numbers...
100gal x .30% is 30 gal of water out and in..

SO HOW MUCH ARE YOU REALLY CHANGING OUT AT 10%??  100gal x .10= 10 gal of water out/in.. THIS IS NOT ENOUGHT OF A WATER CHANGE TO DO YOU ANY GDOD..

I suggest you start to do bigger water changes WEEKLY, clean the filter WEEKLY not just change the pad.. BUT clean the fitler BOX too.... NOW this is not possible with canister filters.. but the remains of the food wil contaminate the filter faster.. cleaning them more often may be necessay to maintain a good lower NITRATE reading....Feeding only every other week may help you here... Beef heart is very messy...

I do recommend that you do a 30% which is 30 gal soon.. then do 25% every week..
I use a 30 gal tough trash can to mix my water in..

YOUR pH is fine.. Don't mess with it....this can cause more problems later if it crashs on you..

DO you test your NITRATES?? With Oscars, this needs to be keep under 20ppm.. with the foods you are feeding this is going to climb dangerously high.. Once you start to do bigger changes and dont' fjeed so much fozen foods as this may be good for them, it fouls your water faster.. feed only right before a water change so you can control your nitrates better..

O and we are in chat so come on in.. IT is on the main page at the top on the right...

Also you might want to remove the NEW oscar and see if your other one wil perk up.. could be another same sex and that is not good.. any time you place 3 of any species together, you are going to have problems.. best to see if this is the case or the one not eating may die of starvation soon.. some species, do intemidate others that much..

Hi,
I checked the water for pH. ammonia, nitrites and nitrates.
You are right - the nitrates are very high, about 80 ppm.

I've done a large water change and will retest and take your advice on weekly changes.

I'll let you know if he perks up!


Thanks,
Stacy

how did the pH and other test do?? sometimes a tank with high reading on any can also afect the pH..
Weekly water changes wil help you here to bring them down more.... Dont' do less then the 25% weekly to help with the nitrates.. Your other oscar may or may not perk up.. As I said, a new oscar may intimidate him enought to make  him sulk to the point of starvation..    a 100 gal tank is not that big for 3 oscars.. Glad you are on the right track for more water changes.. this should help THE OSCARS out tremendlessly..