hello fellow reefers i just put up a frag tank and its been going good ... the only weird thing is that its been hard to control the calcium its a regular 30 gal tank ... the calcium had been at 500 for 2 months straight without me adding any calcium powder or additive etc ... all i have is zoas and some acans in the tank evolution leds from reefkoi 200 watt 24k ones and two hang on filters all the other water levels are all fine im very puzzled pls help and i have also done weekly water changes for two months and still getting 500 :angel: