Calcium & Magnesium

[Sharkbiter]

Has anyone ever had your tank not use calcium & magnesium. My calcium Is 530 and magnesium Is 1610. I have not done a water change in 2 weeks and it's not going down. Last time I did a water change my calcium was 510 and magnesium was 1600 before I did the water chance. Instead of going down it's going up??? Alkalinity is 8.35 dkh. Any ideas would be great I have mostly zoa's but have some hammers, and frogspawns, also have some gloves and xenia. Everything is growing and doing great well accept my candy cane that I just added to my tank a week ago. My tank is fairly new started it first of June, it's starting to show some purple coralline algae finally. is everything as it should be? I'm kind of new to corals, I've had fowlr tanks but this is my first time with corals.

 

[fishroomlady]

far from an expert here but I'd be sure on the results (what test kit?) and have you checked the results against another test or had your LFS check to compare? What type of salt are you using? based on what you have, I would expect to see some usage of calcium and magnesium.

 

[nicodim55]

My Cal is at 780 Alk at 10 dkh

 

[mike007]

Your salt mix could be raising your levels when you are doing a water change. Your tank Is probably not consuming these elements fast enough to notice a decrease.What salt mix are you using?

 

[Tek]

Switch to regular Instant Ocean. Your tank is not requiring enough to use the more expensive salts with higher parameters.

The only time my tank stopped using CA was after a crash but ALK was dropping fast when it started to recover. It was a mknth after before CA started dropping 10ppm a day but then again I keep mostly SPS.

 

[Sharkbiter]

I use Instant Ocean Reef Crystals. I have since I started my tank. When I do water changes I change 35 gallons. I do that every 3 weeks.

 

[NanaReefer]

Something is definitely amiss with those numbers!! Calcium 510 and 730?!! Unless your dosing something or topping off with SW, I'd say your test kits are bad or your doing/reading them wrong.

 

[Sharkbiter]

I use Hanna digital for the calcium and have double checked it with API and nutrafin... all 3 are within 10 points... magnesium is red sea pro... I bought all from BRS about 1 and a half months ago... I haven't double checked the magnesium but calcium I have tripped checked... I don't get it!!

 

[Tek]

RC and large water changes will do it. You don't have the coral load to use it all. Do less water changes unless you have high nitrates or switch to regular IO salt.

 

[Randy Holmes-Farley Verified Community Expert]

I'd just stop worrying about it.

If you are not needing to supplement alkalinity, calcium and magnesium won't noticeably be declining. The salt mix has plenty for your system, and I personally wouldn't even bother to measure them until alkalinity declined.

 

[nicodim55]

Something is definitely amiss with those numbers!! Calcium 510 and 730?!! Unless your dosing something or topping off with SW, I'd say your test kits are bad or your doing/reading them wrong.

Why do you assume that we're doing it wrong or there's something wrong with our test kits? Why don't you read some of my other posts and you will see that I tested an LFS's water with my tester. We're all here trying to get some help so we don't need anyone telling us we're not doing something right.

 

[nicodim55]

I'd just stop worrying about it.

If you are not needing to supplement alkalinity, calcium and magnesium won't noticeably be declining. The salt mix has plenty for your system, and I personally wouldn't even bother to measure them until alkalinity declined.

Thank you Randy that's exactly what I'm doing

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome

Happy reefing.

 

[nicodim55]

You're welcome

Happy reefing.

Well, Randy here's my updated reading with my CA-660 as of today. It was at 700 last Sat weird but... The only thing I've done was added a lot of hammer corals and other LPS's, upgraded from a 40 breeder sump to a 70 gal sump and corals are still happy I guess the hammers are consuming the the calcium for their skeletons.