marineland 350 canister filter with zeo and carbon. I also stuff it with a little extra sponge for bio. I recently been raising temp to 84 and dosing with salt and quick cure. The spots in them are big and mostly on tail and side fins. I really starting to think its something else besides ick. I bought a ro and been using that water and a little of filter tap and that don't help either. ph is 6.8 to 7.0. could this be bacteria?