Sponge Question

[TAZ]

Merry Christmas all,

We were in J&L on the weekend and they had these really vibrant blue sponges (sorry but I forget the name of it), My wife loved the color so we picked one up. Unfortunately, now that it is at home it has lost most of it's color and I am not sure why. I have it in a high flow area of the tank, somewhat shaded from the direct light. On top of the problem with this coral, the day after I added the sponge I woke up to a very cloudy tank. I am running carbon right now to try and clear it up, but it is talking a long time. I did a round of chemical tests this morning, and everything looked good. I am just wondering if the cloudy tank has anything to do with the health of this sponge? I have been searching the internet for info on sponges, but am not finding a ton of information. I plan on doing a 20% water change in the next couple days (mixing water tonight), but am worried that the sponge is hurting the tank. Has anyone else had any similar experiences with sponges? Any feedback would be really appreciated.

Thanks
Martin