false readng?

Wiz · Dec 17, 2014

Hey, I've been trying to balance calcium and alkalinity. Been using baked baking soda and reef calcium. Can dosing one give a false reading on the other? I still havnt gotten to read those articles yet. With xmas and all. I will though. Also how high can calcium go up until it causes trouble? Thx

phillrodrigo · Dec 17, 2014

The higher alk goes the lower the calcium. So yes it can.

phillrodrigo · Dec 17, 2014

Actually it's not a false reading though

Randy Holmes-Farley · Dec 17, 2014

Unless you have fine particles of calcium carbonate in the water (which a few products do add, such as Purple Up), there should be no false reading issues.

Wiz · Dec 18, 2014

So my calcium was dropping like crazy while I had my alk up to get rid of dinos. (Finally gone). So I started adding calcium while still dosing baking soda at the same time. Or in intervals I should say. The calcium would not go up. I stopped dosing the soda since the dinos were gone. Now my calcium tested around 740! Alk was at 7.8. So I am now dosing the soda again to get alk back up. If one is dependent on the other there must be a balance. Or numbers that will hold for both. What are they. I wanted to keep my alk up. Between 9-10. Can I do that without having a low calcium. The soda I'm dosing now is lowering the calcium? What is t he balance? Will the temp calcium of 740 hurt anything?

Randy Holmes-Farley · Dec 18, 2014

Unless you push one unusually high, you generally can maintain about any combination of normal calcium and alkalinity values.

Wiz · Dec 18, 2014

Your a man of few words randy

you must get tired of answering the same questions. The only thing I can't get from your answer is dangerous levels. The 740. What is too high or low for calcium? And also alk. I know the targets. But what are the extremes? If you don't mind.

Randy Holmes-Farley · Dec 19, 2014

I recommend calcium to be 350-450 ppm, but higher levels seem not to be any concern except for increased abiotic precipitation of calcium carbonate. Lower than 350 will start to impact hard coral growth.

I recommend alk to be 7-11 dKH except in a ULNS system where 7-8 dKH is better. Much her higher than this range may be undesirable for some creatures and will accelerate precipitation quite a bit. Lower than 7 dKH will greatly slow hard coral growth.