Sani Marc 29-18315-90 Perfect Logic 900mL Spa Foam Away this fast-acting spa defoamer eliminates foam and suds in spas and hot tubs. Cloudy or foamy water can indicate a chemical imbalance in your water, adding a touch of Foam Away can prevent long term damage or corrosion to your spa’s parts. Keep you water clean and clear with Sani Marc spa care products.