Calcium Rising With No Dosing!

drew.pen · Jul 23, 2019

Greetings everyone,

Long story short, my tank has been sitting at 530ppm calcium for months. Im at the point where I am only dosing the alkalinity portion of ESV bionic. Alk is stable at 8.5dkh, mag 1450, ph 8.4. I use Tropic Marin Pro Reef which i can confirm is 430ppm using my Hanna Checker. I performed a 35% water change yesterday and obtained a reading of 499ppm afterwards. Then, today it came in at 530 and 541ppm.

My tank is composed of realreefrock, im starting to suspect it leaches calcium. Should I make a greater effort to water change my way to victory? How could it rise so quickly again with mo dosing?

ZaneTer · Jul 23, 2019

Tank looks great. It’s not bothering the corals so it shouldn’t bother you.

Rilo · Jul 23, 2019

Nice tank. I'd look more into why you're having a sudden increase in calcium without dosing or water changes. Could it be your test kit acting up?

drew.pen · Jul 23, 2019

I was doubting my Hanna checker originally but since it gives me accurate readings for my freshly mixed saltwater I have come to the conclusion that it is accurate.

This tank is 9 months old and for the first half of its life it was a steady 460ppm. This was maintained by dosing Tropic Marin’s all-for-reef supplement. I ran out unexpectedly and had switched to 2part for a quick week, and in this time I managed to spike up the calcium to 530. Its been there for months, despite weekly water changes of 10-20%. Ive switched back to 2part dosing just with zero calcium component dosed. This had NO impact on my high calcium. I am still dosing 20ml of alk a day to meet the demand- so the uptake is there. Only about half my sps are actively growing so it seems like im suffering from some imbalance.

Since the 30% water change only made a detectable drop for about 24 hours, im considering trying a 60-75% change.

saltyhog · Jul 23, 2019

It has to be leaching somewhere. Is Reel Reef rock made from concrete?

tqpolo · Jul 23, 2019

Hanna checker is known for high reading due to how sensitive it is if you don't rinse and/or use clean deionized water. Secondly, you're just chasing numbers. It doesn't do any harm, leave it alone.

drew.pen · Jul 23, 2019

I did use portland cement to weld my scape together, perhaps its the culprit.

Im aware of the sensitivity of the checker. I go to great lengths to ensure my glass test tubes are cleaned with deionized water and wiped down with a micro fibre cloth, ensuring they are finger print free. There is slight fluctuation in readings, but only by a couple of ppm. Mind you guys, i blow through the reagent packets and bottles. These test results have been repeated dozens of times with various bottles of reagent.

If it was testing error, i dont think id be getting accurate readings for my fresh batches of salt water, nor when i test right after the water change and see there is an impact in my high readings.

Things might look “okay” but I was seeing much greater growth at 460ish than I am in the 500’s. I know the common advice is to not “chase numbers” but isnt correcting a definite imbalance equally as important?

Would rising my alkalinity higher than 8.5ish be advised if I am unable to reduce my calcium?

drew.pen · Jul 24, 2019

New batch of saltwater from Tropic Marin Pro mixed up to 517ppm calcium last night. Totally unsure how to handle this issue. I guess i will never dose calcium again... maybe in a few months i will see a drop in my levels? Im unable to dose any of the calcium component of esv, so im also missing out on the traces added to it that arent being supplemented now that im only using the alk half of the 2part.

If i stop dosing alkalinity then i see a huge daily dkh drop... weird how theres no drop in calcium.

Even tho i trust my hanna checker, i will swap it out for a salifert or redsea test kit- its my only option left as if i leave this issue unaddressed then the balence between trace minerals and alk/cal/mag will become even farther than natural sea water.

Mkeller088 · Oct 20, 2021

drew.pen said:
New batch of saltwater from Tropic Marin Pro mixed up to 517ppm calcium last night. Totally unsure how to handle this issue. I guess i will never dose calcium again... maybe in a few months i will see a drop in my levels? Im unable to dose any of the calcium component of esv, so im also missing out on the traces added to it that arent being supplemented now that im only using the alk half of the 2part.

If i stop dosing alkalinity then i see a huge daily dkh drop... weird how theres no drop in calcium.

Even tho i trust my hanna checker, i will swap it out for a salifert or redsea test kit- its my only option left as if i leave this issue unaddressed then the balence between trace minerals and alk/cal/mag will become even farther than natural sea water.

I’m having the same issue. I use tropic Marin with 400 calcium. My calc is 530, no dosing. Alk is set up for 10.0.
this is so strange. I used life rock, and Marco mortar.
how’s yours now? It’s been since 2019 I see. Mine is 1 year old.

TastyScrants · Dec 31, 2022

Did you find a cause? I have this same issue. I think it’s bound somewhere and is leaching.

Randy Holmes-Farley · Dec 31, 2022

BLineDisaster said:
Did you find a cause? I have this same issue. I think it’s bound somewhere and is leaching.

That is not generally a possible cause, since any significant boost to calcium from any material we use will typically boost alk through the roof (2.8 dKH for each 20 ppm of calcium released).

Test error, overdosing of calcium, rising salinity, addition of calcium that you are not aware of, and top off with tap water are by far the most likely culprits for calcium, that seems to rise over time.

What additives do you use (if any)?

TastyScrants · Jan 1, 2023

Randy Holmes-Farley said:
That is not generally a possible cause, since any significant boost to calcium from any material we use will typically boost alk through the roof (2.8 dKH for each 20 ppm of calcium released).

Test error, overdosing of calcium, rising salinity, addition of calcium that you are not aware of, and top off with tap water are by far the most likely culprits for calcium, that seems to rise over time.

What additives do you use (if any)?

Other than TMC frozen gamma foods the other things going into my tank are: Redsea foundation A, B, C, NOPOX, Phosguard.

The calcium head in my doser has been off for 3 weeks while I wait for calcium to drop back to the range I want. Ive also checked I haven’t mixed up any dosing lines, I’ve had my calcium result (>500ppm) verified by an LFS test.

Salinity has been solid at 35ppt for weeks, within the 0.2ppt accuracy of my salinity checker.

I top off with RO I make myself. I use Redsea blue bucket salt - I will test it today when doing my WC to check the levels are correct. But it would need to be pretty massive as my 10% WC is 15L.

TastyScrants · Jan 1, 2023

Just tested 15L of Redsea blue bucket made up in RO to 35ppt. Calcium (salifert) measuring >500ppm

I’ll check Redsea batch data if I can find it and edit thsi post with it

TastyScrants · Jan 2, 2023

So I got the batch data, looks like the issue was regarding the salt separating out. I gave it a vigorous mix then tried making up more saltwater and this resolved it.