Calcium hydroxide no alk?

mrmole83 · Dec 7, 2015

Hello!

I have a 700l tank and was dosing kalk everyday for about 10 days already but noticed droping alk. So i tested the solution coming out of my calcium hydroxide with salifert alk tester. I came out undetectable. The test water just remain green/blue and did not change color after 1 ml of reagent.

Is something wrong with my calcium hydroxide powder?

Randy Holmes-Farley · Dec 7, 2015

The alkalinity of saturated limewater (2 tsp calcium hydroxide per gallon of fresh water) will be about 114 dKH, so unless you diluted it before testing, it will take a lot of reagent to get to the endpoint.

How much were you dosing each day and was the alkalinity stable before dosing?

mrmole83 · Dec 8, 2015

My alk was stable but low at 6 dkh. Now after dosing 100ml per day it has dropped to 5.5 dkh. What i did change recently within that 10days is rowa phosphate absorber.

Randy Holmes-Farley · Dec 8, 2015

100 mL per day is not a useful addition. It adds hardly anything (less than 0.02 dKH per day). Most people replace most or all evaporated water with it. I'd try 2-3 liters per day and see what that does. You may need more than that.

Randy Holmes-Farley · Dec 8, 2015

FWIW, be sure it add it very slowly.

This has much more on limewater:

What Your Grandmother Never Told You About Lime by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-01/rhf/index.htm

mrmole83 · Dec 8, 2015

Oh wow thank you. I will do

mrmole83 · Dec 13, 2015

Randy can i learn about your fish quarantine method? I have not been successful once. My fish just drop within the first week of qt.

Randy Holmes-Farley · Dec 13, 2015

mrmole83 said:
Randy can i learn about your fish quarantine method? I have not been successful once. My fish just drop within the first week of qt.

I have usually bought from very reputable places which do quarantine, such as the Live Aquaria Divers Den.

In that case, my "quarantine" is usually like an additional sump that is attached to the main tank. It is not isolated from the display, but I would isolate it if a problem arise and I needed to treat. Otherwise, I basically just set up a small tank with some live rock and macroalgae. I don't have a set time I use.

mrmole83 · Dec 23, 2015

Alk has increased to 7.0 with kalk! Thank you Randy.

mrmole83 · Dec 23, 2015

Is this reference reliable?

Randy Holmes-Farley · Dec 23, 2015

I don't know as I've not seen it before.

What do you want to use it for?

I know this one is accurate, but it calculates different things about limewater:

http://reef.diesyst.com/chemcalc/chem_calc3.html

mrmole83 · Dec 23, 2015

I found that one when i was trying to figure out how much of what was i adding

mrmole83 · Dec 23, 2015

Will saturated kalk lose potency if stays in tightly coverted container randy?

Randy Holmes-Farley · Dec 23, 2015

mrmole83 said:
Will saturated kalk lose potency if stays in tightly coverted container randy?

As long as it is unstirred and covered, it is fine for at least a month. Stirring drives in CO2 faster and causes faster depletion.

mrmole83 · Dec 30, 2015

Randy Holmes-Farley said:
As long as it is unstirred and covered, it is fine for at least a month. Stirring drives in CO2 faster and causes faster depletion.

Randy. Alk has increased to 7.0 with kalk. Should i measure calcium? It should be balanced right?

Randy Holmes-Farley · Dec 30, 2015

The calcium should hardly have changed (unless a water change altered it), but its certainly fine to measure it.

In the long term, limewater to maintain alkalinity exactly causes calcium to rise a bit since magnesium takes the place of a small portion of the calcium ions in the coral skeletons.

mrmole83 · Dec 31, 2015

Randy Holmes-Farley said:
The calcium should hardly have changed (unless a water change altered it), but its certainly fine to measure it.

In the long term, limewater to maintain alkalinity exactly causes calcium to rise a bit since magnesium takes the place of a small portion of the calcium ions in the coral skeletons.

So do i have to supplement calcium if keep dosing lime like this?

Randy Holmes-Farley · Dec 31, 2015

It may provide all calcium and alkalinity that you need (it does in my system), but if the tank uses more than you provide via the limewater, then you'll need to add more of both of those (some do, using a two part or a CaCO3/CO2 reactor along with the limewater).

mrmole83 · Dec 31, 2015

Randy Holmes-Farley said:
It may provide all calcium and alkalinity that you need (it does in my system), but if the tank uses more than you provide via the limewater, then you'll need to add more of both of those (some do, using a two part or a CaCO3/CO2 reactor along with the limewater).

If the calcium drops means that the alk will drop along with it right? At least to a certain level and then it get imbalanced. Is that true?

Randy Holmes-Farley · Dec 31, 2015

A calcium drop of 18-20 ppm means an alkalinity drop of 1 meq/L (2.8 dKH).

If calcium drops and alk does not (and nothing is added), then the calcium measurement is in error, or it was from a water change.