Thanks again everyone. I am a belever in the water changes as well i do them mainly was seeing what exactly it does besides the trace elements etc. i do love the anology jimd very good one and throws everyone else's right in there as well. I do water changes on a bi weekly rate of about 25% i drain out the old into a marked container dump it/mix my fresh and pump it back in useing a aquaclear 70 (old pwrheads from my first setup)