New dry rocks-Can they leach out alk and calcium?

[Klyph]

I’ve set up a new red Sea 625. It cycled a month or so ago. I’m running a refugium, carbon reactor, a protein skimmer with a C02 scrubber. I have six fish and about 15 small frag’s in the tank. I used Red Sea coral pro salt. I’ve been dosing via kalkwasser mixture of 2 tsp/gallon in my ATO

Temp - 79
salinity -1.024
Nitrate - 6
Phosphate - 0.0
Ph - 8.1
Mag - 1370
Calc - 330
DkH - 4.5

the bottom two numbers keep plummeting. I’ve tried adding additional kalkwasser into the tank. I just put in 10 oz of alk 2 part liquid today, and it dropped from 4.9 to 4.5.

I’m completely out of answers. The only thing I can think of is the rock is consuming it. Is there any way that the new (still white) Marco dry rock I used in this new tank could be leaching out the calcium and alk? I used a lot of mortar in therock.

 

[Triple.T]

What test kits are you using for the tests?

 

[Klyph]

What test kits are you using for the tests?

Hanna checker for alk, Red Sea for calcium.

 

[Triple.T]

What are the frags? Sps, LPS, softie? Hard saying what's eating all your alk and calcium.

 

[Klyph]

A couple of each. Such a small sampling in a 150gal tank... just doesn’t make sense that they’d be consuming that amount in a day. I just poured 12 oz of Red Sea alk liquid, and it went down the over that 24 hour period.

I’ve been pouring thru all the prior threads. I know mag can be an issue, so I made sure to get that up in the upper 1300s.

again, my question is, can new rocks leach it out of the water?

 

[Triple.T]

If you mean can rock absorb nutrients, then the answer is absolutely they can! That's what makes live rock so beneficial and rich in coralline algae and life.

Just hard to believe it would take THAT much. Do you have any other tests to compare to? Maybe a trip to a LFS if that's an option to have them double check the accuracy between 2 different tests?

 

[Klyph]

I had done it earlier, and they confirmed the lower numbers. Is it fair to assume that the rocks will get saturated at some point?
I know a lot of folks are using these man made artificial rocks now. It’s weird nobody else is noticing this problem.

 

[AcanthurusRex]

Yes Marco rock would dissolve in a CARx. This would add Alk and Ca to the water.
No Marco rock will not bind Ca and Alk from aquarium water.

 

[SliceGolfer]

Plenty of posts out there by Randy Holmes Farley stating that new tanks for the first 8 months will consume Alk and CA as they mature, even with no coral. Normal, it’s part of the maturing band stabilization stages of a tank.

 

[Klyph]

Plenty of posts out there by Randy Holmes Farley stating that new tanks for the first 8 months will consume Alk and CA as they mature, even with no coral. Normal, it’s part of the maturing band stabilization stages of a tank.

ok, so I just need to keep dosing crazy levels consistently? Would y’all recommend kalkwasser, the Red Sea Foundations liquid, baking soda, what?

 

[Klyph]

Yes Marco rock would dissolve in a CARx. This would add Alk and Ca to the water.
No Marco rock will not bind Ca and Alk from aquarium water.

Using the term leaching was probably confusing. I meant to ask whether new rock could suck the calc and alk out of the water. I’m just trying to wrap my head around where it’s all going.

 

[AcanthurusRex]

BRS 2 part or TM All for Reef. Don't "dump" things into the tank.
Neither of the two tanks I set up using Marco rock did anything as you are describing.
It is difficult for what you are describing to occur. The only way I can think of this occurring is precipitation. I suspect water changes would be sufficient at this point with your tank.
I use the Hanna and RedSea tests and they both have worked well. The RedSea will read low as the reagent ages; replace if expired.
Maybe @Randy Holmes-Farley can comment.

 

[Klyph]

BRS 2 part or TM All for Reef. Don't "dump" things into the tank.
Neither of the two tanks I set up using Marco rock did anything as you are describing.
It is difficult for what you are describing to occur. The only way I can think of this occurring is precipitation. I suspect water changes would be sufficient at this point with your tank.
I use the Hanna and RedSea tests and they both have worked well. The RedSea will read low as the reagent ages; replace if expired.
Maybe @Randy Holmes-Farley can comment.

When I apply the Red Sea 2 part alk and calc, I do them separately. Ill put the alk in a zip log bag, hang it off a light, and poke a hole with a toothpick. Low tech dripper. It usually takes about an hour to drip 8oz.

 

[Yevoc]

Is there a sand bed in it?

 

[Klyph]

Is there a sand bed in it?

Yes, mid sized grain, special grade caribsea. Little over an inch deep. I do see some precipitation in the sand bed.

 

[Klyph]

Yes, mid sized grain, special grade caribsea. Little over an inch deep.

@Randy Holmes-Farley , I would love to hear your thoughts on my question. What causes a new tank to use up so much alk and calc? Is it the new dry rock? Or is something abnormal going on with me?

 

[Randy Holmes-Farley]

Using the term leaching was probably confusing. I meant to ask whether new rock could suck the calc and alk out of the water. I’m just trying to wrap my head around where it’s all going.

Bare calcium carbonate can bind additional calcium and alkalinity, essentially acting as seed crystals for more precipitation until something like magnesium, phosphate and organics clog up the surfaces.

 

[Yevoc]

Bare calcium carbonate can bind additional calcium and alkalinity, essentially acting as seed crystals for more precipitation until something like magnesium, phosphate and organics clog up the surfaces.

This is why I was asking about the sand bed. The only time I had nonsensical cal/alk usage was when I had a sand bed glue itself together many years ago. OP check if the sand is clumping.

 

[Klyph]

Bare calcium carbonate can bind additional calcium and alkalinity, essentially acting as seed crystals for more precipitation until something like magnesium, phosphate and organics clog up the surfaces.

Hmm, that makes sense, and could be the issue. To confirm, would my response be to do a thorough cleaning of the sand bed, or should I leave it alone? (Thanks so much for the response, by the way)

 

[Randy Holmes-Farley]

Cleaning it doesn’t help. Stop dosing anything for a few days, Keep alk low 7 dKH when you resume dosing, and use bicarbonate to do it. Don’t aggressively lower phosphate, and don’t use gfo. After a while it should stop if you are feeding and such.