[FragIt Dan]

+1 on what Myka says... I would have to respectfully disagree as well. I think Myka nailed it with his comments below...

Originally Posted by Myka

No it won't. He was only at 11 dKH. Dosing 50 ppm calcium from <300 ppm calcium absolutely will not cause precipitation. If he added 120+ ppm calcium in one shot to 11 dKH alkalinity, then yes that would probably cause precipitation. 11 dKH is not very high. Go read my first post. In fact, the Randy Holmes-Farley article you posted even lists 11 dKH within his recommended concentration.

Plus, I don't believe his pH reading was accurate. pH of 8.7 is very difficult to achieve in reef aquaria. Besides, alkalinity doesn't directly affect pH anyway.



Calcium and alkalinity work together like a teeter totter. If you add calcium, alkalinity will go down. If you add alkalinity, calcium will go down. I guarantee if he raises his calcium slowly from <300 ppm to 420 ppm in 3 doses over the next 2 days his alkalinity will drop from 11 dKH to about 9 dKH, and there will not be any precipitation.



This is simply not true. Getting precipitation on pumps will not cause them to die prematurely. Leaving precipitation on the pumps, just like leaving "natural" buildup on the pumps by not cleaning them often enough can cause premature failure, but it's not like you flick the switch and the bulb bursts.

Dan