Perplexed at sudden alkalinity increase

FrugalReefer

Valuable Member
View Badges
Joined
Oct 2, 2021
Messages
1,552
Reaction score
11,128
Location
San Diego
Rating - 0%
0   0   0
Need help diagnosing why my alk experienced a sudden significant increase from 7.85 dkH on 1/11/24 to 9.3 dkH as of today 1/17/24. Here are some of my numbers since November. Even though the numbers don't reflect it, I aim to keep my alk between 7-8 dkH.

11/26/23 - 7.5 dkH
12/2/23 - 8.0 dkH
12/7/23 - 8.0 dkH
12/14/23 - 7.85 dkH
12/21/23 - 7.85 dkH
12/28/23 - 8.15 dkH
1/5/24 - 8.15 dkH
1/11/24 - 7.85 dkH
1/17/24 - 9.3 dkH

All values were taken using a Salifert test kit which has an expiration of 9/2027 and measured at the same time each day, at around 7:00-7:30pm. I performed the most recent test twice to make sure user error in the testing process could be ruled out and sure enough, I got the same result. As far as other parameters during the same time frame, pH swings from 7.7 at night to around 8.1-8.2 during the day, temp has been in the range of 80-82F, salinity around 1.025-1.026, nitrates around 2, phosphates at around 0.03.

Some information on my system, it is an SPS dominant Waterbox nano with a sump. I know most of you are going to hate and disagree with it but I carbon dose and have been for awhile to keep my nutrients in check and also to feed my corals the extra bacterioplankton. I run only a cheap skimmer and I have xenia in my sump also as filtration. I don't run carbon, GFO, UV, filter socks, etc. I feed my fish flakes, pellets and frozen twice a day on a rotational basis (flakes-pellets day 1, frozen-flakes day 2, pellets-frozen day 3, repeat). The only things I feed my corals are ESV 2 part, Brightwell Coral Amino and Brightwell Replenish. Lighting is suppled by a 150W Nicrew Hyperreef, flow by the return nozzle and some Jebaos.

The only things that I have changed recently are

1/10/24 increased frequency of amino dosing slightly
1/14/24 decreased daily amount of vodka dosed slightly

I implemented these changes because some dinos and small patches of cyano have started to show up and so far the existing dinos and cyano haven't spread. Hopefully they'll disappear over time. Other than that though, I got this jump in my alkalinity and I can't figure it out. I've only been reefing for 8 years but I don't see how this could effect the daily alkalinity consumption of my corals, unless I'm missing something. On second thought though I've read that a decrease in nitrates could cause an increase in alkalinity. But my nitrates have been steady at around 2. Any ideas?
 
OP
OP
FrugalReefer

FrugalReefer

Valuable Member
View Badges
Joined
Oct 2, 2021
Messages
1,552
Reaction score
11,128
Location
San Diego
Rating - 0%
0   0   0
Can you clarify if you are dosing alk, so we can tell if we are looking at reduced demand, or an actual increase in alk?
Yes I dose ESV 2 part calcium and alkalinity on a daily basis if that’s what you mean. I am currently dosing, manually, 27 ml of each.
 

John K

Community Member
View Badges
Joined
Jan 21, 2011
Messages
76
Reaction score
94
Location
ma
Rating - 0%
0   0   0
Could nitrate bottoming out / hitting zero explain a rise in Alk (with everything else staying constant).
 

Coinzmans Reef

Active Member
View Badges
Joined
Jul 14, 2020
Messages
317
Reaction score
439
Location
Parlin NJ
Rating - 0%
0   0   0
My tank goes thru periods of high consumption to low consumption. I can go from 50 ml a day to 15ml a day of alk, this swing takes days to weeks. My Calcium also follows the swing. I manage the swing via the apex. I have noticed growth spurts in the corals in conjunction with high consumption. My Coraline algae seems to almost completely disappear from thee back wall (falls off in sheets during low consumption) and than starts the growth (high consumption) cycle all over again.
 

Randy Holmes-Farley

Reef Chemist
View Badges
Joined
Sep 5, 2014
Messages
72,100
Reaction score
69,741
Location
Massachusetts, United States
Rating - 0%
0   0   0
Yes I dose ESV 2 part calcium and alkalinity on a daily basis if that’s what you mean. I am currently dosing, manually, 27 ml of each.

Something apparently reduced demand. Could be lower pH, some element limiting growth, some irritant the water, etc.
 
OP
OP
FrugalReefer

FrugalReefer

Valuable Member
View Badges
Joined
Oct 2, 2021
Messages
1,552
Reaction score
11,128
Location
San Diego
Rating - 0%
0   0   0
I think I may have overdone it with the vodka and my nitrates are bottoming out despite the fact that I get a faint color on my Salifert Nitrate test kit. My plan is to now slowly and gradually reduce my carbon dosing over time so my nitrates get up in the 5-10 range. If that means completely weaning off carbon dosing so be it. Thanks for everybody's help and insight.
 

HAVE YOU EVER KEPT A RARE/UNCOMMON FISH, CORAL, OR INVERT? SHOW IT OFF IN THE THREAD!

  • Yes!

    Votes: 32 45.7%
  • Not yet, but I have one that I want to buy in mind!

    Votes: 9 12.9%
  • No.

    Votes: 26 37.1%
  • Other (please explain).

    Votes: 3 4.3%
Back
Top