i bought some phosguard by seachem.it says on the bottle that it does not leak phospates or silicate back into the water.also that it can be dried and reused till exhausted.what are your thoughts on that?i dried them after 4 days of use,they have a slight brown color to them.i put the used phosguard and swished it around in some ro water before drying,and tested it with my phosphate test.it come up around .01 should i reuse?thanks