I never take it out of the tank so I don't run into that issue. If you know how to work with them while in tank, you wont have any issues either. And until recently, I always used the cheap magfloat ones you can get form petsmart. They do a great job and don't have the magnetic force as some like the aglaefree magnavors or similar. I do have one of the phiranas now, and have no issues sticking some algae under it.