Need guidance with testing and dosing

bh750 · Oct 25, 2017

Longtime hobbyist that's never tested for much other than NO3, PO4 and PH. This is b/c I've always had other problems (nuisance algage, dinos, accidents) that prevented me from getting far enough to keep many corals. Embarrased to say, but the truth.

Anyway things are finally going well. I've watched a BRS TV video on test kits several times and have a feel of what's important to test and how often. Now I just dont know what, exactly, to do for each. I bought a gallon of Kalkwasser from BRS but other than that I dont have much.

Here's my current readings:

These are monitored by an Apex controller

Temp: 78-79
Salinity: 34-35
PH: 7.9 - 8.1
ORP: 329-373
Alk: 6.8
Cal: 410
Magnesium: 1350
NO3: ~15
PO4: 0.00 - 0.06

I know Alk and Cal are low. I was dosing the Kalkwasser in my ATO for awhile before I even really understood what to do.

My system is ~ 300g and right now consists of about a dozen nice fish along with:

- Some Palys & Zooas
- 1 ricordia
- 3 BTAs
- 1 large frogspawn
- 1 chalice
- some GSP

Is there a good thread or article on understanding this and a good place to start?

EriksOasis · Oct 25, 2017

http://reefkeeping.com/issues/2004-05/rhf/

Here’s a good article on water parameters and the importance of these levels. With such few corals I wouldn’t think you would need to start dosing until you add a lot more. But testing to see where your levels go from water change to water change are important to give you an idea of how much your levels are getting depleted.

PatW · Oct 25, 2017

You have a big aquarium and not much in the way of hard corals. Hard corals construct their skeletons from calcium carbonate. As they grow, they will deplete the levels of calcium and alkalinity from the saltwater.

I have hard corals and I test alkalinity daily. The corals can deplete alkalinity pretty quickly. Saltwater has more calcium in it so the levels drop slower. I test that less often. Hard corals will also absorb magnesium but if smaller quantities. For me, water changes seem to maintain magnesium just fine.

I use BRS two part for dosing and so far I am dosing by hand. As my coral frags become colonies, I may switch to running dosers.

For the tests, I use Red Sea Pro for Ca and ALK. I use Salifert for magnesium. Red Sea is not consistent for me for magnesium. Salifert has a good ALK test. I have not tried their Ca test.

Randy Holmes-Farley · Oct 26, 2017

How much solid calcium hydroxide have you been putting in your top off water? Maybe boosting it a bit will solve the alk and calcium needs, and I don't see another need at the moment.

bh750 · Oct 28, 2017

Randy Holmes-Farley said:
How much solid calcium hydroxide have you been putting in your top off water? Maybe boosting it a bit will solve the alk and calcium needs, and I don't see another need at the moment.

Thanks Randy. So I put in 1 TBS per gallon of topoff water. Definitely raised my PH levels from 7.9 to 8.3 ish. (Forgot to mention the other reason I tried this was to raise PH to stave off Dinos, which at the moment are not present).

So thanks everyone. Makes sense that since I dont have alot of calcium dependent corals, calcium is not a worry. So I'm gonna read the article above, but guessing Alk being low is ok. I think I'll learn that proper Alk levels effects how Calcium is absorbed. thanks all!