Learning my tanks parameters

unclephatpat42 · Dec 28, 2014

So I just bought an automatic doser but first I'm trying to figure out how much cal/alk/mag my corals use up.
I have a 50 gallon with a 20 gallon sump, only filled half way. Corals I have only one bubble coral, elegance coral, a few zoas, one small colony of xenia and a colony of green star polyps. I run gfo in a brs reactor and a protein skimmer.

So as of Friday 12.26.14 my parameters are

Cal - 450
Alk - 13.3 dkh
Mag - 1320

As of today 12.28.14
Cal - 400
Alk - 9.8
Mag - 1200

Has those corals consumed that much in two days? Can a gfo reactor strip the tank that much? Nothing happened to the tank, no water changes either. I also noticed that when I supplemented the alk just right now I began to precipitate, what may have caused that to happen?

unclephatpat42 · Dec 28, 2014

I also have a bag of chemipure in the sump also

unclephatpat42 · Dec 28, 2014

And I dosed the alk first, 20 min before the calcium and mag

Randy Holmes-Farley · Dec 28, 2014

What you saw as a precipitate was probably just transient magnesium hydroxide that redissolves and is no concern.

Did you add anything between those two measurements?

If not, then calcium did not drop that much and magnesium didn't change more than a few ppm. Those two changes are probably testing error.

unclephatpat42 · Dec 28, 2014

I'm sorry I'm not quite understanding your question. Are u asking if I dosed any cal.mag.alk in the past two days?

Randy Holmes-Farley · Dec 29, 2014

Yes. Or did a water change in that time.

unclephatpat42 · Dec 29, 2014

Ohh no, I've done nothing to the tank in those two days.

Randy Holmes-Farley · Dec 29, 2014

Then the calcium and magnesium didn't really drop that much. If the alk drop is accurate, the calcium didn't drop more than about 25 ppm and the magnesium didn't drop more than 5 ppm.

unclephatpat42 · Dec 29, 2014

Just to simplifying things for my understanding, magnesium is used so that cal and alk won't buffer each other out? In another forum I was reading they said they kept mag really high at like 1500, and Cal around 420 and alk at 9.0dkh just so the cal and alk won't deplete as fast, what do u think?

Randy Holmes-Farley · Dec 29, 2014

You want magnesium for many reasons, including that organisms use it, but there no need to keep it above natural levels of about 1300 ppm.

Magnesium can help reduce the rate of abiotic precipitation of calcium carbonate on things like heaters and pumps.

unclephatpat42 · Dec 29, 2014

What would u recommend my target parameters should be? I'm going for a mix of lps and softies.

Also how do I go about finding how much I should dose a day to keep these stable parameters? So far I've been testing every two days for a week n a half so far.

Randy Holmes-Farley · Dec 29, 2014

Here are my recommendations:

https://www.reef2reef.com/forums/re...-coral-reef-aquarium-randy-holmes-farley.html

How much has the alk dropped in a week or so?

unclephatpat42 · Dec 29, 2014

Sunday 12.21.14 0000am
Cal 390
Alk 9.5
Mag 1280
Phosphate - 0.36
Ph - 8.4

Monday 12.22.14 1120
Cal - 440
Alk - 11.2
Mag - 1400

Tuesday 12.23.14 1540
Cal - 440 ppm
Alk - 4.9 meq 13.7 dkh
Mag - 1320 pm
Phosphate - 0.16

Friday 12.26.14
Cal - 450 - 0
Alk - 9.8 - dosed 50ml
Mag - 1240 - dosed 140ml
1hr later
Alk - 13.3dkh
Mag - 1320

Sunday 12.28.14
Cal - 400 - dosed 40ml
Alk - 9.8. - dosed 50ml
Mag - 1200 - dosed 210ml
1hr later

Cal - 450
Alk - 12dkh
Mag - 1400

Randy Holmes-Farley · Dec 29, 2014

You are dosing too much.

Once the alk is down to 9 dKH or less, Try dosing 10 mL of each part each day for several days and see where the alkalinity stabilizes.

unclephatpat42 · Dec 29, 2014

Okay will do

Randy Holmes-Farley · Dec 30, 2014

Let us know what happens. It will likely need another adjustment.

unclephatpat42 · Dec 30, 2014

Randy say for instance I did a water change and it lowered my parameters lower than what my target, say Cal 390/alk 8/mag 1200.

Would I dose each element separately to reach my target or keep dosing the both cal/alk 5 ml unil it reaches my target.