Alkalinity Question Please help

[frags]

Hi Guys

I have a new tank it is a 20 gallon JBJ shallow tank with sand and dry rock. The tank took 2 months to cycle and I used Dr. Tims. The tank has been cycled now for 6 weeks.

The question is why does my Alkalinity drop so fast?..... A little about the tank

Salinity 1.025
Alkalinity 5.16
Calcium is at 500
Mag at 1350
PH Day is 7.8 night is 7.6
Temp fluctuates between 76-78

I use Coralife salt and I change 3 gallons about every 10 days. The new salt mix mixes at 9dkh before I add to the tank.

Tank inhabitants

rock flower anemone
1 chalice frag
12 assorted snails
I macro algae
3 sexy shrimp
1 rodactus mushroom


Things I have ruled out...

The RODI water is fine 6 stage Spectapure with no TDS come out the other end
Alk test results confirmed with 2 test a Hanna kit and a Red sea Kit.

NOTE
I do see a hazy cloud in the tank and it is not Calcium precipitating before someone offers that. I cant tell if its the sand bacasue the tank is so shallow or if its possibly a bacteria bloom? It has been going on for about 3 weeks.

Help would be great!

 

[Randy Holmes-Farley]

It is normal to need to supplement alkalinity. Water changes are not normally adequate.

 

[Randy Holmes-Farley]

I'd look to initially add some baking soda, and then look to a two part or limewater to supplement calcium and alkalinity.

 

[frags]

What I don't understand is what can be consuming so much The tank is so new? I dont have a bunch of corals?

 

[frags]

I'd look to initially add some baking soda, and then look to a two part or limewater to supplement calcium and alkalinity.

What I don't understand is what can be consuming so much The tank is so new? I dont have a bunch of corals?

 

[Randy Holmes-Farley]

Coralline can consume as much as 2-3 dKH per day. The chalice will also consume some , as will nitrification if nitrate is increasing.

 

[frags]

Coralline can consume as much as 2-3 dKH per day. The chalice will also consume some , as will nitrification if nitrate is increasing.

I am not new to reefing I had a 100 gallon total system with a 40 breeder display growing just SPS. For some reason I thought such a little tank I could keep up with 33% water changes a week and not growing SPS. I Understand the Chalice a LPS will consume but I didnt really think about the water volume I am dealing with! When I filled the tank with live rock and sand the tank only truly holds 13 gallons.

I could see the nitrification like you said.

If the white cloud was a bacterial bloom do you think that could be eating the alk up?

 

[Randy Holmes-Farley]

No, bacteria do not impact alkalinity.