I know Spectrapure sediment filters are absolute rated and I believe Buckeye Field Supply also carries them too. I still say if you are getting phosphates in your finished water you need to be looking at your RO membrane and both the resin and residence or contact time in your DI filter since those are the two pieces that remove the phosphates. Some membranes are better than others and some resins are better than others at removing certain things. The sediment and carbon filters only protect the RO membrane and do not remove much by themselves other than particulates and chlorine.