Well, this morning as I just woke up, I went to check on my oscar and he appears to have these really bad looking white areas, I don't know if he damaged himself or its a disease. Over the past week, I did notice him sulking in a corner and not eating quite as much as he used to. I've been doing lots of water changes, as much as 50% every 2-3 days. I will get the ammonia/ph/nitrate read outs for you guys in about a hour, the water temp is 29c.

Sorry for the poor quality, he wasn't very co-operative and was getting freaked out by the camera.

This is a shot from last night, I didn't notice it then but you can see some of the spots on the sides.


The rest of shots are from today





Any help/information would be very much appreciated.

take a close look, do they look like cotton wool. ie raised above skin level as it looks like fungus to me. as you have changed the water recently your reading may be good now. what were they a wk ago? poor maybe what would explain a fungus. it certainly don't look like battle damage to me. I would get those water results asap just in case things are still poor. if they are good treat for fungus and keep that water in good condition.

The most important thing we need to know is what your water conditions are like, without knowing it's really difficult to guess why this has happened. It does look like fungus to me. Were there any injuries in the vicinity of the head before this happened? You will need to check for ammonia, nitrites, nitrates and pH. When carrying out water changes, have you been using a water conditioner?

Amonia - <0.3
NH - 0.5
NH - 0.5
PH - 5
Water conditions have stayed more or less the same over the past weeks.
Yes, I have been using water conditioner and I still let the water sit as long possible before using it.
It does look somewhat like cotton wool.
I do water changes 2-3 times a week usually, just only to around 30% or so, I went extra this week because of the unusual behaviour.
There were no signs of it prior to now and I usually sit next to the tank for quite a while each day looking at him. He's never had any injuries before either.
Looking at him some more, there even appears to be a spec on one of his eyes

A somewhat better pic:

This could well be down to water conditions but it is really hard to say that for sure. That almost certainly looks like a fungal infection site as soon as possible get yourself a fungicide medication and that should help.

Please confirm whether your pH of 5.0. How big is the tank? Also, what type of filtration have you got? How long have you had to fish for?

Sorry for all the questions, I'm just trying to establish why your water conditions are not so good. It might be a good idea to get some Prime as well. This will neutralize ammonia and nitrite. It also might be an idea not to do so many water changes, it may be a 40% water change, and then leave it a few days and let the waters settle down

its a 40 gal tank, I've had him for... I want to say 8 months, maybe a bit more. (I know the tank is small, I have a new tank thats in the cycling stages that he will be moved to)
I only have one of those PH strips that you stick on the glass, I can't say whether its very accurate or not but I've been trying to find a proper testing kit for ph.
I have a Cascade canister filter rated for a 150gal tank and a 2nd one rated for a 75 gal tank (unfortunately even both still leave debris on the base sometimes).
I also use a gravel vac when doing water changes to help get that extra bit of debris out.
What is "Prime"? (google isn't helping me there)
I'll do another change today and leave it for a few days then.
I'll try to get the fungicide med today if I can catch the LPS open.
Thanks for the help, I don't mind the questions, whatever extra to help him.

Yes, 40 gallons is a tad too small so the sooner you can move the Oscar, the better it will be.

I would suggest a liquid test kits, something like aquarium pharmaceuticals, I've been using them for quite a few years and they have always been very reliable.

Prime is a multifunctional solution that neutralizes chlorine and turns ammonia and nitrite into a non-toxic form. It's always handy to have if you run into water quality problems.

Have you turned your filter off for any period of time lately?

I would definitely suggest a fungal medication, treat your tank and hopefully it will help clear this up.

As for why your water conditions are not so good, I really couldn't say from here. Carry out a sizable water change before you medicate the tank and then don't change the water until you have finished medicating. After you finished medicating, carry out another water change.

x2 i would double the dose of prime. it won't harm your fish if you over dose but it will help to remove the ammonia/nitrites etc. feed very little if at all. looks like you have lost your cycle from the filters as you have 2 I find that difficult?

I would do things a little different than Penn. its up to you what you follow. i would continue water changes and add medication to the new water to replace that removed. if you do things the other way your ammonia/nitrite may rise alarmingly. it will be a pain to carry out the changes and add meds to all that water but on the bright side your tank isn't that large.

It appears I did lose the cycle, about a week and a half ago the power went out for a few hours in the night so it may have happened then.
I'm going to head to the LPS soon, hopefully they'll have both fungicide and prime, although, I've never seen or heard of prime before.
Thanks for all the info guys.

Just remember if you carry out water changes when you are medicating the tank, you are actually removing some of the medication, so that defeats the object at the end of the day.

Well, I did a water change and added the med a couple hours ago and he certainly seems more active now to say the least.
As I suspected, the LPS didn't have Prime, I did however get ammonia fix and well "De-Nitrate" which is in a pellet form (like carbon) which I'm unsure if I should use or not, I'm think maybe a week inside one of the canisters and then throw it away, any suggestions on that?

I just took a look at him, looks like most of it has cleared up so far!