Help request with Alk and Ca dosing

[moobiecow]

Am I dosing Ca and Alk incorrectly?

I have a 43 gallon Red Sea system that i've recently upgraded to and have been attempting to dose for the first time. My tank was upgraded from a 29 gallon with a HOB sump/filter, and it fell into a bit of neglect over the past 2 years. I've never really dosed before with the 29 gallon, and making a real effort to learn with the new system.

Tank contains a pair of clownfish, medium brain coral, medium frogspawn, and a small colony of zoas with 15ish mixed CuC of snails/scarlet hermits.

Currently my readings are:
Alkalinity: 6.72
Calcium: 440
Magnesium: 1480

All readings were done with the red sea test kit.

I've been dosing Red Sea 15 mL (i'm estimating .1125 dkh) of red sea Ca and Alk per day, and have not touched mg because every time I add any amount, it skyrockets my mg levels in the tank. I'm swapping to sodium bicarbonate because my pH hovers around 8.3/8.4 and dosing sodium carbonate spikes it above that range. The last time I took a reading was a few days ago on the 13th, and it was at 7.56, so i'm confused as to how my tank is consuming that much alk in that short time period.

Do I dose the sodium bicarb do appropriate levels and add in the same amount of Ca? Do I continue to hold the Ca dosing at 15mL/day if i'm happy with the Ca levels? I'm also very confused as to why my mg is still high without a water change and adding anything to the tank after a few weeks.

 

[Kostas G.]

You dose Alkalinity and Calcium separately. Your Calcium is levels are good but your alkalinity are not. You should increase your alkalinity dosing(right now I would increase by 50% but at the same time break up the daily dose to as many as I can and check alkalinity once a day) to slowly increase it to 7,5 or 8 but very slowly, like 0,05 dKH per day. Then you would decrease dose till you find the dose you keep it stable.

Do you have any new rocks in your tank? New rocks tend to mess up the consumption rates in the beginning

 

[moobiecow]

No new rocks, but new sand was put in when I set up the tank after moving houses ~3 months ago. I just added some bi-carb in (30 mls of the BRS solution I mixed) and it increased dKH by .7 (I broke up the required dosing to get it to where I wanted in the BRS calculator to by 4 doses, but i'm assuming that I need to go a lot smaller and slower for the future dosing.)

 

[Randy Holmes-Farley Verified Community Expert]

You seem to be doing fine.

Which Red Sea products are you talking about dosing?

Why did you switch to BRS?

 

[moobiecow]

I was dosing Red Sea part A and B, but switched to BRS sodium bicarbonate since my pH was hovering around 8.35 and I didn’t want it to spike above 8.4 with a dose of sodium carbonate. Should I get my alk up further to around 8-9? My frogspawn hasn’t look too happy since moving tanks and hasn’t fully extended for the past few months. Brain and zoas seem to be fine though.