Back to the drawing board...ALK and Cal

revhtree · May 12, 2017

I just got home last night from RAP (took some time off) and went right to testing the tank. I had my Apex DOS dosing 425ml of ALK and CAL daily. After testing I have found that my ALK dropped about 1.5 DKH to 7.5 DKH but my Calcium was steady at around 450.

Ideas?

Ps. Used two different test kits to confirm.

GatorScott · May 12, 2017

Does a drop like that affect your tank if you get it corrected in a timely manner?

revhtree · May 12, 2017

GatorScott said:
Does a drop like that affect your tank if you get it corrected in a timely manner?

It can and I have a couple Montipora showing the effects.

austinl · May 12, 2017

revhtree said:
I just got home last night from RAP (took some time off) and went right to testing the tank. I had my Apex DOS dosing 425ml of ALK and CAL daily. After testing I have found that my ALK dropped about 1.5 DKH to 7.5 DKH but my Calcium was steady at around 450.

Ideas?

Ps. Used two different test kits to confirm.

Hey Rev,

I'm not sure but in my humble little tank I currently dose more alk than calc even though they are supposed to be dosed the same with amounts in theory.

I'm not sure what your using for your two part but I assume my diff in dosing amounts could be explained by potency of each solution that I mix myself.

BlueCursor · May 12, 2017

You are dosing 425 ml daily? Unless you have a ton of fast growing corals and quite a few clams, that is a ton of Ca/Alk dosing. It's probably precipitating out.

How old and how big is your tank? Some tanks are hard to get Alk above 7.5. For a year I had to just accept my Alk was 7.5. My issue was mostly over doing biopellets, but that's another story.

cjd · May 12, 2017

I would first watch to see if alk dose turns on. Maybe it skipped a dose or two while you were away . Power failed can cause this ???? I would first look into making sure the pump is working correctly (calibration off ??) . Manually dose to bring the levels back up . Check daily to see if it was just a fluke thing or dosing needs to be adjusted .

BlueCursor · May 12, 2017

+1 on checking everything. You need to first figure out why you are dosing sooooooo much.

re76 · May 12, 2017

I would agree with everyone else that you are dosing far too much and experiencing precipitation which is why you are dosing more.

I struggled a lot with this issue as well. For me what eventually solved it is switching to a sodium bicarbonate based 2 part. Specifically the aquaforest balling method.

revhtree · May 12, 2017

I am using BRS Two Part and it has been dosing correctly.

The tank is about 425g total water.

I don't know if I am just dumb or what but I can't get this figured out! Ha!

GoVols · May 12, 2017

re76 said:
I would agree with everyone else that you are dosing far too much and experiencing precipitation which is why you are dosing more

+1

ReeferMaddness843 · May 12, 2017

I just started using brightwells kalk +2 and with a 1tsp per gallon of top off have had a 0.0 drop in any of the big 3 over 5 days now. It's on a pretty well stocked, coral wise, 80 gallon. May help hold that stability.

cjd · May 12, 2017

revhtree said:
I am using BRS Two Part and it has been dosing correctly.

The tank is about 425g total water.

I don't know if I am just dumb or what but I can't get this figured out! Ha!

I would bring the levels back up and let the tank and dosing pumps do its thing and test again in 2 or 3 days and evaluate from there . It could have been a dosing hiccup while you were away . EVERYTHING happens while you are away!!!!

GoVols · May 12, 2017

@revhtree
Please bring your alk up slowly and within the daily max. dose or (lol) we'll be back at your all parameters are dropping thread.

Thanks, GoVols

GatorScott · May 12, 2017

cjd said:
I would bring the levels back up and let the tank and dosing pumps do its thing and test again in 2 or 3 days and evaluate from there . It could have been a dosing hiccup while you were away . EVERYTHING happens while you are away!!!!

What a RAP buzzkill

GoVols · May 12, 2017

GatorScott said:
What a RAP buzzkill

lol
Maybe not, if he found an awesome cal reactor down there.

Brew12 · May 12, 2017

Any sign of grayish looking pebbles or deposits forming on your rock or sand bed?

jwshiver · May 12, 2017

What is your Magnesium level?
I am currently dosing 56.2 ml of BRS two part in net 100 gallons.
My DKH has leveled off in the last few weeks. I have started daily dosing of Magnesium daily and it seems to have helped. It seems like every time I leave for more than four days my ALK drops. As a matter of fact something always goes wrong right before I leave or while I'm gone. The last time it dropped to 6.38 https://www.reef2reef.com/threads/alkalinity-dropped-1-24-while-on-vacation.297021/.
SPS where not happy for awhile and started some tissue necrosis, but it eventually stopped. Hope you don't have any problems.

Zoarderer · May 12, 2017

I don't know what I'm talking about but could it be the magnesium? I don't even dose because I read things first but what I remember is that Cal, Magnesium and Alk is all linked together. If one is low is hard to keep all others balanced.

Randy Holmes-Farley · May 12, 2017

ReeferMaddness843 said:
I just started using brightwells kalk +2 and with a 1tsp per gallon of top off have had a 0.0 drop in any of the big 3 over 5 days now. It's on a pretty well stocked, coral wise, 80 gallon. May help hold that stability.

Just keep in mind that the magnesium part of that product is nonsense.

Randy Holmes-Farley · May 12, 2017

Here's more info from another thread:

The magnesium in kalk+2 is not useful and incredibly misleading. Here I detail how not useful it is:

https://www.reef2reef.com/threads/best-kalk-stirrer-brands-types.225280/

from those who do not care to switch to another thread, here's the short story:

1. Magnesium is not soluble in limewater, so it will just sit on the bottom

2. The amount present in kalk+2 (Brightwell claims 0.15%) is not nearly enough to meet the demand for magnesium based on that amount of calciuma nd alkalintiya dded (which might, however, be adequately met by water changes with a salt mix with plenty of magnesium).

3. The amount of magnesium in kalk+2 is LESS than is present in many bulk brands of calcium hydroxide as an impurity.

I did a calculation in that thread that, even if one ignores basic chemistry and incorrectly assumes all of the magnesium that Brightwell claims to be in the product gets into the tank water, at a dosing of 1% of the tank water volume daily using saturated limewater, the amount of magnesium added per day is too small to be noticed (0.02 ppm per day).