于 2005-07-12 11:51 I have a same problem but my problem is red algae. TY2 please check P04 la, value should be below 0.02ppm. I only can keep this value to 0.1ppm this value is high. Use bestest Active carbon because poor quality will release PO4 and use Ca(HO)2 solution to 沉積 PO4 la ( Ca3(PO4)2), it can keep in safe value.