I have two tanks both with Aqua clear filters on them and on the top of the filter a white residue always builds up and it usually floats on top of the water in the filter as well. Does anyone else have this problem and do they know how to reduce it or prevent it?? any help would be appreciated

thanks

Is it like white scummy / gummy stuff? If yes then that is normal: it builds up on everyone's tank equipment. It's completely harmless and wipes off easily (and no - I have absolutely no idea what it is, though I suspect it might actually be a bacterial growth).

If it's white hard stuff which is difficult to scrub off then that is limescale, which is mineral deposits from hard water. Again, not harmful but it takes more work to get it off.

yup thats the stuff
thanks a lot for your help