Hi guys,I have owned two oscars for a year and a half now. I have noticed that one of them is loosing colour.Is this something normal to the fish or do I have a problem? Thanks to all.

Hi there could be many reasons for this. tell us how big your tank is, how big are your O's, what are you feeding them? sorry for the questions, I know others will be asking you others.

no one could ever tell. but as a precautionary measures,
i suggest water test immediately. if water is good, then
check the feeding practice. we should not keep ourselves
sitting pretty well when observed any unusual things.

i do know that oscar change colors from time to time, either
because of mode, health conditions, varied foods and growth
stages.

My tank is 4ft(L),1.5ft(H),1.5ft(W) they are both 9" and I always give them good quality food like Tetra Doromin sticks, and occasionally some frozen bloodwarms.To be saying everything I have a nitrate problem (No3) which I am dealing with.

sounds like a 75gal tank? do a 25gal water change, and another tomorrow ck the nitrate again and keep doing the changes until the nitrates are down to 0. this is the life of an Oscar tank.

I have upload a photo of what I'm talking about if it works.

pretty. like Paul said when O's are passive they can look pale. just make sure your water parameters are perfect. 0 ammon, 0 nitrites, 0 nitrates, ph 7+, and temp 78-80. water changes lower the nitrates. nitrates are poisonous to all aquatic fish. good luck OFL is a great place for help. I hoped I helped. if not someone will come along and cover what I didn't.

actually your tank works out to be 55 gallons which is too small for one o let alone two. this is probably the reason you have a nitrate and hith problem.
i would recommend getting a larger tank say something in the 110 gallon range.until then lots of water changes will help in reducing the nitrates and also be the first step in treating the hith. also imho this is also tied to the fading colour of your oscars.

good luck with your o's and keep us posted.