My reef isnt using calcium or magnesium

James Mikell · Apr 25, 2019

Ive had my reefer 250 going for about 8 months now and with working 75-90 hour work weeks, water changes have stopped for the last 4 months. My tank over all looks good and everything is healthy and growing. After fearing that my parameters had fallen low i bought a salifert test kit for the basics. Cal measured out at 450 alk at 6.7 and mag at 1550. 3 weeks later i tested agsin and got the same results except alk had dropped to 6.5 but that could have been test error. I don't dose anything so just wanted to know if its normal for a reef tank to not use any cal, alk, or mag. I have since started dosing alk per my local lfs suggestion to get it back up to 8.3-8.5 but been doing so slowly. Here is a picture of my tank.

James Mikell · Apr 26, 2019

Anyone?

MrObscura · Apr 26, 2019

I believe there's only 2 reasons for the elements to appear to be consumed out of balance. One, waterchanges and/or dosing actually threw off the balance. Or testing error.

And I think as Alk drops consumption slows down in general so it all might have slowed down.

Also, there's far more cal and mag in the water so even while it's being consumed in a balance matter it will always seem slower just because there's more of it.

I wouldn't start dosing one or the other only, that's just going to throw things out of wack. High mag and cal won't hurt so just get them all were you want them and then dose all equally. Though you probably don't need to worry about Mag if you do water changes.

Arricefe · Apr 26, 2019

I had posted a similar question as you and was advised to adjust alk and leave everything else alone, I would say try that but don't go overboard like I did.

My Calcium and Mag are both off the charts according to my Red Sea test, 500 and 1500, and my alk was in the same range as yours 6.5 ish. I dosed the Red Sea foundation b to raise alk and I may have overdone it, I tested yesterday and alk was at 12! Oops! Visually everything looks good, if I didn't know my parameters I would say my tank is doing great! I'm not going to do anything but test everyday at the same time for a while to see if anything changes. BTW I'm in the early stages of what I plan on a mixed reef so I have some SPS, LPS and ZOAs and they all are looking good so I'm sure they're consuming calcium but it's been above 500 for a while.

James Mikell · Apr 26, 2019

Arricefe said:
I had posted a similar question as you and was advised to adjust alk and leave everything else alone, I would say try that but don't go overboard like I did.
My Calcium and Mag are both off the charts according to my Red Sea test, 500 and 1500, and my alk was in the same range as yours 6.5 ish. I dosed the Red Sea foundation b to raise alk and I may have overdone it, I tested yesterday and alk was at 12! Oops! Visually everything looks good, if I didn't know my parameters I would say my tank is doing great! I'm not going to do anything but test everyday at the same time for a while to see if anything changes. BTW I'm in the early stages of what I plan on a mixed reef so I have some SPS, LPS and ZOAs and they all are looking good so I'm sure they're consuming calcium but it's been above 500 for a while.

Yeah im going to just adjust my alk to where i was advised and then test every few days. So far the cal and mag haven't moved from their original numbers from 3 weeks ago. Everything looks happy but i couldnt keep any of the small sps frags i had bought. So time will tell