Zis bio ZB-300F

[rugby143]

Hi everyone 

Just bought the ziss bubble bio, I have an air line attached 1 to my sponge filter 1to my ziss but at the moment the ziss is only circulating a small amount of the media and the majority are jst standing still up top, please advise 

[Ken Dyer]

The Ziss will tumble more as the media ages, but to me it sounds like you may be just at the border of having enough air to drive it. I would make sure the hard airline on the side of the filter is well seated and not sticking up to much, that the twist valve is fully open if you are using it, and then give it a week or two to see if the media tumbles better once it gets more established. If after a week or two it still isn't tumbling as much as you want you may need to upsize your air pump. (never hurts to have a backup air pump in a pinch so the current one wouldn't go to waste)