Young tank losing alk & calc

[BeejReef]

So, probably not serious, but figured might check in w experts.

65g DT, 30g sump, 70sh gallon TWV. Tank is less than two months wet. 5 weeks from end of cycle.
Two clowns, 3 pj cardinals, 7 snails
5 softy frags, 6 lps frags, 1 sps frag. They do show some growth, but modest.
10lbs of established live rock w some coraline, 50lbs of dry (now with a nice green color) and some marine pure media balls in sump. Chaeto fuge. I do weekly 10g water changes with HW Reefer.

Salinity 1.026
PH 8.4
Nitrate 1
Phosphate 0

I just bottomed out on nutrients and have trimmed my chaeto.

Question is, my alkalinity fell from 9.4 to 8.4 DKH and Calcium from 425 to 380 in 48 hours, along with a 30pt drop in Magnesium? Where is my alk and calc going?

Prior to this, Calcium had been stable and I had to buff alk once or twice. Happy to see consumption but was under the impression the tiny frags don't consume hardly any.

ty


PS, if you'd care to armchair QB, how would you address bottoming out on nitrate and phosphate. I feed twice a day, a little more than the fish can eat in 5 min. Flake in the a.m., Mysis in the evening.
1) feed more
2) part time skimmer instead of FT
3) Trim chaeto
4) reduce chaeto photoperiod

 

[Ron Reefman]

Question is, my alkalinity fell from 9.4 to 8.4 DKH and Calcium from 425 to 380 in 48 hours, along with a 30pt drop in Magnesium? Where is my alk and calc going?

Prior to this, Calcium had been stable and I had to buff alk once or twice. Happy to see consumption but was under the impression the tiny frags don't consume hardly any.

PS, if you'd care to armchair QB, how would you address bottoming out on nitrate and phosphate. I feed twice a day, a little more than the fish can eat in 5 min. Flake in the a.m., Mysis in the evening.
1) feed more
2) part time skimmer instead of FT
3) Trim chaeto
4) reduce chaeto photoperiod

Don't fret over that drop in alk as 8.4 dKH is fine. Have you tested the water you use to do water changes with before you add it to the tank? That's a sharp drop in Ca and Mg but they are easy to add back in. For the time being, I'd just keep monitoring it and adding in alk, Ca and Mg as needed. I have a 40g DT (80g system) stuffed full of zoas and rock flower anemones with only a few small lps and sps frags.

My consumables go down like this in 3 or 4 days:
alk from 10.0 dKH to 8.5 dKH
Ca from 450 to 410
I run Mg high all the time and rarely test.

As for your low nitrate and phosphate levels (I never even test mine unless something crazy happens in the tank), I think your solutions #3, then #1, then maybe #4 (much less effective IMHO) and #2 I don't think is very much involved in nitrate or phosphate removal.

 

[saltyhog]

The calcium drop is not consistent with the alkalinity drop. Did you repeat your testing to make sure there was no testing error?

If it's real, the only things I can think of are coralline algae growth (seeing any?) or precipitation (look on pumps, heaters). Also you didn't mention what your Mg level was, just the drop. If it's low it will contribute to Alk and Ca stability.

 

[cracker]

Check the sand to see i it could be clumping .

 

[Ron Reefman]

The calcium drop is not consistent with the alkalinity drop. Did you repeat your testing to make sure there was no testing error?

If it's real, the only things I can think of are coralline algae growth (seeing any?) or precipitation (look on pumps, heaters). Also you didn't mention what your Mg level was, just the drop. If it's low it will contribute to Alk and Ca stability.

Did you mean to say "stability" or "instability"?

 

[saltyhog]

Did you mean to say "stability" or "instability"?

LOL...yeah, lack of stability!

 

[saltyhog]

Check the sand to see i it could be clumping .

Good thought, another place that precipitation often occurs.

 

[BeejReef]

Don't fret over that drop in alk as 8.4 dKH is fine. Have you tested the water you use to do water changes with before you add it to the tank? That's a sharp drop in Ca and Mg but they are easy to add back in. For the time being, I'd just keep monitoring it and adding in alk, Ca and Mg as needed. I have a 40g DT (80g system) stuffed full of zoas and rock flower anemones with only a few small lps and sps frags.

My consumables go down like this in 3 or 4 days:
alk from 10.0 dKH to 8.5 dKH
Ca from 450 to 410
I run Mg high all the time and rarely test.

As for your low nitrate and phosphate levels (I never even test mine unless something crazy happens in the tank), I think your solutions #3, then #1, then maybe #4 (much less effective IMHO) and #2 I don't think is very much involved in nitrate or phosphate removal.

ok, so I guess that's on par. It's just the first time I've seen any real drop and was surprised. For weeks the numbers never budged.

 

[BeejReef]

The calcium drop is not consistent with the alkalinity drop. Did you repeat your testing to make sure there was no testing error?

If it's real, the only things I can think of are coralline algae growth (seeing any?) or precipitation (look on pumps, heaters). Also you didn't mention what your Mg level was, just the drop. If it's low it will contribute to Alk and Ca stability.

I doublechecked Alk, not Calc. I'll check it a second time tonight.

 

[BeejReef]

Check the sand to see i it could be clumping .

What would that look like? Little white clumps? If so, what would cause that (I have 1330 magnesium)? What could be done to prevent it?

Testing inconsistency is a possibility with me. I'm new to the hobby and titrations (red sea). Still, I'm pretty methodical.
Would love it it was coraline starting. In a dozen or so spots on the rocks, I can see pencil-head sized whitish dots.

I put the tank on the low dose of Kalkwasser after the low levels were discovered last night. Prior to that, had just been water changes

 

[cracker]

Hey William. I can't explain the chemistry It happens whan the sand sucks up the alk,Ca .This causes the sand grains to fuse together & turn into rock. Small sized at 1st bur soon these all fuse together making large slabs .
This is happening in my big tank. I can't figure it out either. All I knew was the tank was sucking this stuff up ! It ended up in the sand which is full of big slabs of the stuff. I'm following to see what others say .