I have Florabase in a 25 gal tank that's a month old. I didn't rinse it. Any movement causes bad clouding, but it settles and clears up. Soft, light, very easy to plant in. Lowers my pH by 0.4, KH by 3. Plants grow well, but it's supposed to deplete after about a year. This is just an experiment for me, only time will tell if it's a good choice.