Depleting Calcium

Plunder · May 14, 2020

My tank has been depleting calcium at a fast pace. It seems to be consuming about 20-40 ppm a day. Will this eventually level out? I figure it might be due to the Coraline algae trying to take hold and is sucking it up along with my corals. I did some google searches but was hoping to see what the community thought. I also had a question about boosting my alk levels with "Fluval Sea Alkalinity" as the instructions are a bit vague, like how much exactly does 1 ml raise X amount of gallons? Some insight on my parameters right now is Cal 400, Alk 9, Salinity 1.025-1.026, Mag 1400, ammo 0, nitrite 0, nitrate 0. I have a Fluval 13.5g running for a little more than a month with 2 small clowns, small fire dart goby, a scarlet cleaner shrimp, a peppermint shrimp, 6 micro hermits, 12 snails 2 species , 6 micro stars , a chiton? not sure what it is lol, and a bunch of pods live in the garden and rock. I also planted some sea grapes and some type of red macroalgae (got from IPSF). I also have two small stony corals, GSP (who had a hydrogen peroxide dip recently and still hasn't opened), and two leather mushrooms with some zoas and some Coraline algae boosting tiles. I could also use help identifying the two stony corals, as they were a gift and have no clue what they are.

Appreciate it!

Reefing Madness · May 15, 2020

@Randy Holmes-Farley

Saltyreef · May 15, 2020

Your consumption of alk, calcium and magnesium should be recorded over a 5 day period testing @ same time each day.
This will tell you your tanks baseline elemental consumption.

As far as products. Starting out I would stick with a high quality 2 part additive + magnesium.
Like ESV B-ionic alkalinity, calcium and magnesium.

You can hand dose these daily to keep up with consumption until you get comfortable then get a 3 head auto doser

Randy Holmes-Farley · May 15, 2020

A true 20-40 ppm calcium decline would be accompanied by a 2.8-6 dKH per day alk decline since the only sink is calcium carbonate.

If you are not seeing a substantial alkalinity decline, the calcium issue is just random test measurement error,a nd I'd just keep watching it longer to see things average out.

Plunder · May 15, 2020

Randy Holmes-Farley said:
A true 20-40 ppm calcium decline would be accompanied by a 2.8-6 dKH per day alk decline since the only sink is calcium carbonate.

If you are not seeing a substantial alkalinity decline, the calcium issue is just random test measurement error,a nd I'd just keep watching it longer to see things average out.

Thanks, I'll try a different test kit. API test does seem a bit inaccurate, especially now that I use them a lot.