Well I found out something the hard way as usual. I just shoved my floss/filter media into the pump and yes I kept extra in there just in case I needed it. If you do this beware I heard a very strange noise coming from one of my HOBs and had no clue what it was. It seemed to be running fine so I just dismissed the noise as nothing. Well cleaning day rolled around and it was time to check all the floss and rinse if needed. I find in that
HOB that the floss had gotten into the side where the impeller is and yes it had wrapped around it. It did take a few minutes to get it all out but the HOB is fine WHEW. My son had a great idea to prevent this and it is now in use in most of my HOBs and will be in the rest of them as soon as I get enough stuff to hold it in. We took two of the plastic filter frames that fit the HOB and put the floss in the middle with them clipped together with the plastic clips from the school supply section. I am going to get some of the plastic mesh for some of the others to prevent this from happening again and just clip it into place.