Reef nutrition

Tanks Alk consumption has increased 30% over the last 15 days

Blaise006

Supporting Member
My tank is approaching a consumption rate of about 5 dkh a day. It got me thinking about alk swings in sps tanks.

What are your alk numbers for a mixed/sps tank?

How much is the intraday swing?
What level do you keep alk?
Size of system?
Amount of sps?
Alk consumption?

Would really like to hear everyone’s stats.
 
5 sounds like a ton...sure you’re not getting precipitation somewhere?
Totally agree. Feels like a ton, I’m sure it’s precipitating some of that somewhere. Unfortunately, I’m not sure what I can do to stop it.
PH tops out at 8.42 around 6pm. I’m sure that’s when a lot precipitates out.
 
What are you using to test? Cause I probably need it.
Neptune Trident

A6E7182C-19B7-4789-8F62-FA8732BFC0C3.png
 
Do you have sand?

Is your sand turning into concrete?

I had huge alk consumption in my tank while my sand bed was turning into a giant rock
I’ll double check tonight, but I blew some around while cleaning it a week or so ago. I would say the power heads and return are taking the brunt of it.
I am just not sure what the solution is. Kalk? I don’t like the idea of switching dosing methods. Seems like a recipe to stress the sps :/
 
Are you seeing tons of growth in stony corals?

That picture is from March 31st. It is covering the entire disk and moving down the side as of today. I would say all the frags are growing at roughly the same rate. Not sure how that compares with your experience, I thought it was moderate growth. Roughly 30 frags growing at that rate.
104BFF7E-72C4-41A6-8368-6F53F8B952EC.jpeg
 
i think 5dkh a day is a lot. id get a 2nd reading with a hanna alk checker.

before my calcium reactor, i dosed 50ml of kalk aka pickling lime every hour. 1200ml within 24hours.

How much is the intraday swing?
my swings are 8.2 - 8.6

What level do you keep alk?
i like to keep my alk at 8.4

Size of system?
rsr350 (73g display, 18g sump - 91 total)

Amount of sps?
about 100 sps mini colonies/frags

Alk consumption?
last time i checked, if i turned off my calcium reactor beginning of this year, my alk dropped ~1.6dkh in 24hours
 
Last edited:
5 dkh is huge! I was losing 1.3 - 1.5 a day tops when I had my rugby ball sized hollywood stunner challice, and dosing ~230-250 mL/day of 2 part alk solution. I have a 168 gallon mixed reef with 220 total, currently I am dosing 130 mL/day of alk. I shoot for about 9.0 dKh in my tank.
 
Last edited:
i think 5dkh a day is a lot. id get a 2nd reading with a hanna alk checker.

before my calcium reactor, i dosed 50ml of kalk aka pickling lime every hour. 1200ml within 24hours.

How much is the intraday swing?
my swings are 8.2 - 8.6

What level do you keep alk?
i like to keep my alk at 8.4

Size of system?
rsr350 (73g display, 18g sump - 91 total)

Amount of sps?
about 100 sps mini colonies/frags

Alk consumption?
last time i checked, if i turned off my calcium reactor beginning of this year, my alk dropped ~1.6dkh in 24hours
I do a Hanna check every other day when I get home. I suspect it’s mostly precipitated out when ph hits 8.4. Maybe carbon dosing is an option. Would love to not have to dose so much.
 
5 dkh is huge! I was losing 1.3 - 1.5 a day tops when I had my rugby ball sized hollywood stunner challice, and dosing ~230-250 mL/day of 2 part alk solution. I have a 168 gallon mixed reef, currently I am dosing 130 mL/day of alk
Agreed, it’s way to much. Wish I knew what to do. If I don’t counteract the swings they get to be .5 - .8 dkh swings between peak PH.
PH fluctuates around 8.08 to 8.42 a day.
 
One thing that I find interesting is that the ratio between low ph and high ph consumption is roughly 60% of the total consumption happens during the high ph photoperiod and 40% during the low ph period. Which seems like a pretty reasonable split and not solely indicative of a high ph precipitation event. Obviously just speculation and I’ll update tonight once I can fully inspect the sand.
 
Back
Top