Is my dosing correct?

[Moonfroz]

Hello Guys,

I would like to have your comments regarding my alk, Ca and Mag dosing because I have to dose much more than I was expected since my tank is not ever stock.

I have few corals (2 gorniopora, 2 duncans, 1 sun coral, 2 small torch corals, 2 heliofungia, 3 SPS (small baseball size), 4 small acan frag, 4 small SPS frag) and a bunch of fishes.
None of these corals are big since I started my tank about 5 month ago.

My system is the following: (total water volume is about 250-275 gallons)
Main tank = 180 gallons;
Refugium = 75 gallons;
Sump = 90 gallons.

I have about 125 to 150 pound of very porous live rock.

I am running a Rowa reactor to remove phosphate and a Bio-pellet reactor to remove nitrate.

My current parameters are:
Alk: 9.3 dKH (Target is: 10 dKH)
Calcium: 390 ppm (Target is: 450 ppm)
Magnesium: 1290 ppm (Target is: 1350 ppm)
Nitrates: 0 ppm (Target is: 0 ppm)
Phosphate: 0.05 ppm (Target is: 0 ppm)

The solutions are prepared as following and I am using the Aquaristik product (SR Entreprise):
Alkanility solution: 440 grammes of Sodium Carboate (Soda Ash) per gallon of RO/DI water
Calcium solution : 440 grammes of Calcium Chloride (CaCl2) per gallon of RO/DI water
Magnesium solution : Mix of [440 grammes of Magnesium Chloride Hexahydrate + 440 grammes of Magnesium Sulfate] per gallon of RO/DI water

I am currently dosing using a Kamoer doing pump (3 pumps), I am dosing every hour over the 24h period to get:
for Alk: 225 ml of Alkanility solution per day
for Ca : 250 ml of Calcium solution per day
for Mag: 275 ml of Magnesium solution per day

Since my tank is filled with only few small corals, I was wondering if the amount of solution dosed daily is normal or there is something wrong?!?

Best Regards!

 

[JohnKoz1234]

try target nitrates between .5-.10 for a while you ll see big changes....

 

[Stackemdeep]

I follow RHF and BRS recipe of 5 parts Magnesium Chloride Hexahydrate to 3 parts Magnesium Sulfate, (cups) and then mix with one gallon RODI water.
I believe this avoids a sulfate build up.

Soda Ash is 2 cups per gallon (roughly 453 gr) and Calcium Chloride is 2.5 cups per gallon RODI (roughly 567gr). Your solution might be fine, I would defer to the expert chemists that frequent this forum. Good Luck!

 

[Moonfroz]

try target nitrates between .5-.10 for a while you ll see big changes....

why?

 

[bertoni]

Coralline algae can consume 2-3 dKH per day, along with 20 ppm calcium. The magnesium dosing seems strange, but water changes can change parameters a lot, and making a significant change in the magnesium level takes a lot of supplement.

I'm guessing that the tank is consuming about 1.5 dKH per day, which is reasonable. You could stop the automatic dosing for 24 hours to check that. I'd measure the alkalinity just after finishing a dose, and then at 12 hours, and then at 24 hours. If you dosed by hand for a few days, you could get a better consumption estimate.