oscar fish and green or white fog in tank

Question
Hello,

My name is Noah Calderon and I've done some research on the oscar fish before I purchased him or her ( since I don't yet understand how to tell the difference )and had the tank preped before I perchased him. I have followed what i've read about keeping the tank clean but I seem to be getting a green fog tink or a whtie fog tint. I don't over feed and only have the tank light on at night. I feed my oscar blood worms which he likes and oscar grow. I read that oscars are not timd, though my fish is very scketchy. These are just a few things I have noticed about my oscar. If you can helpwith some of the things I have mentioned. Oh yea, before I forget. My oscar is black with non- straightened oranged stripes. Just last night before I went to sleep I saw that from his mid section and up the orange was replaced with a dim brownish green. Is this normal and is he not doing well? Please help!

Answer
Hi Noah;

Oscars will sometimes have a greenish tint to their skin. It's almost a "sheen" really. Just to be sure he's okay, have the water tested. Ask your fish store to test the levels of ammonia, nitrite and nitrate. Toxin buildup can cause fish to change color and also cause the water to be cloudy. You didn't mention how big he is, what size tank he is in, how long it's been set up, or what kind of filter is on there so I really can't tell if there is a problem. Oscars need at least 50 gallons just for one to grow up in. Oscars grow fast, are very messy and get to be over 12 inches long. They need a good power or canister filter too. If there is an undergravel or internal filter instead, it simply isn't adequate. Oscars are just too messy for them.

All tanks need a weekly 25% water change and gravel vacuuming too. Hopefully you are doing that already. If not, now is a good time to start.

Overfeeding can cause cloudiness as well. Feed your oscar once a day whatever amount it takes for him to eat all of it in about 3 minutes. Oscars are gluttons and can also really make a mess while eating. Excess food should be removed right away so it doesn't foul the water, and feed less next time so there are no leftovers. If the worms are going everywhere as he eats and he can't get them all you might consider a different food. He should get more variety anyway. The worms don't have enough nutrients by themselves, even with added vitamins. A good gel-based or pelleted food is a great basic diet. Feed the worms as a treat.  

If your tank is fairly new (less than 8 weeks) it can also be going through the break-in period. Tanks often become temporarily cloudy during break-in. In case that's going on, here is my web page about it;

http://www.xanga.com/Expert_Fish_Help

At Your Service;
Chris Robbins