Large White Spot, Don't Think It Is Ich....help!

[newbiefishla]

So, my husband changed food on his tank but didn't tell me.  I think I overfed them for a few days --- two fish died.  However, a third hasn't been eating and is hanging out at the top of the tank swimming towards the filter.  He has done this for days.  Watching him yesterday, I noticed a huge white spot on one side (it is about half inch long). We have two other large gold gouramis and a large black angel. 

 

[newbiefishla]

Had to get the video off my phone.  Here it looks more like a burn, but to the naked eye it looks white.  Any ideas or suggestion would be great.  Sorry about the play sign, I had to take a screen shot to get the image. 

 

[techen]

What size is the tank and how long have you had it for?

 

[newbiefishla]

Iy is 55 galloon. We have had it since 05, but we have moved twice with it. The most recent move was in January of 2010.last year we had a lot of difficulties keeping the water balanced, and have all new fish. We haven't added any new fish in about 6 months. Currently, we only have the four fish.

 

[newbiefishla]

Any ideas?

 

[josh63762]

I the picture is not clear at all but from what you are saying I think it could be a fungus add salt touch your tank just in case holding thumbs