Kalkwasser or two part for me?

Ryan15236 · Oct 8, 2015

My tank is a 125 gallon mixed reef tank. I have about 5 lps frags, 3 sps frags and 3 zoa frags in there at the moment. As you can probably imagine my corals don't really put a dent in my Calcium, Alk, or Mag. However I am ever expanding my tank and I will need to start dosing or keeping my parameters pretty stable. I want a mixed reef with a lot of SPS. Maybe even SPS dominated. Right now all I do is a 10%WC every two weeks. I test my calc, alk, and mag weekly and top off any if needed. Right now I also have the BRS 2 part dosing kit without the pumps. Like I said I just monitor and top it off when needed. So should I look into using kalkwasser in my ATO for awhile. This way is cheap and I don't have to buy a doser for awhile. Or should I just continue to manual dose until a doser becomes needed?
Current Levels
Alk-7.8-8.0
Calc-420
Mag-1350

Randy Holmes-Farley · Oct 8, 2015

Do you have an ATO in place now?

Ryan15236 · Oct 8, 2015

Yes I do have an ATO on my tank currently. The tunze osmolator 3155.

Randy Holmes-Farley · Oct 9, 2015

In that case, using an ATO with limewater can be a good choice. That's all I use for my system. You may not need much of the solid calcium hydroxide dissolved in the top off water.

Do you know about how much you evaporate each day?

Ryan15236 · Oct 9, 2015

No I do not. I know that I have an 8 gallon container and probably last me about 8 days. So let's just say a gallon per day for now and I can work on getting a more exact number.

Randy Holmes-Farley · Oct 9, 2015

OK, so if you want to go the limewater/kalkwasser route, I'd try mixing 1 level teaspoon of calcium hydroxide per gallon of top off water and see what that does to alkalinity after a few days. Don't worry about calcium at this point.

Ryan15236 · Oct 9, 2015

Ok so do you think I should go ahead and start adding this to my top off water? Like I said I am really not getting any uptake at the moment from the corals so I just want to avoid doing any overdosing. Sorry, pretty new at dosing and maintaining proper reef parameters. I will go ahead and order some calcium hydroxide from BRS though

Randy Holmes-Farley · Oct 9, 2015

Oh, I thought you were dosing some of the two part now manually. If not, I'd just add 1/4 teaspoon per gallon of top off to get in the swing of doing it and see what happens to alk. I doubt it will go up much, and it might even decline as tad as the pH rises.

Then over time, if the alk seems to not be as high as you want, slowly raise the amount in the top off.

Ryan15236 · Oct 9, 2015

Well I mean I have been dosing a little. However that has been mostly to get the parameters where I want them. I will test my water today and see what the results are. I really don't think I am getting much uptake. Not enough that WC can't keep up with. But like I said I have 3 sps corals and 2 lps corals going in the tank today so that may put a little dent in it. I just order calcium hydroxide from BRS so should be here Tuesday and I will start messing around with it! Definitely going to start slow like you mentioned and work into it.

Calcium Hydroxide or Kalkwasser will raise Alk and and Calcium both correct? I swear I was reading something somewhere else and it said that it didn't raise Alkalinity and that a mixture of Kalk and two part was the best way to do it?

Randy Holmes-Farley · Oct 9, 2015

Ryan15236 said:
Calcium Hydroxide or Kalkwasser will raise Alk and and Calcium both correct? I swear I was reading something somewhere else and it said that it didn't raise Alkalinity and that a mixture of Kalk and two part was the best way to do it?

No that's wrong. It raises both and is all I've dosed in my tank for 20 years.

It adds calcium and alkalinity in approximately the ratio used by corals, which is about 20 ppm calcium for each 2.8 dKH of alkalinity.

What you cannot do it use to to make a one time boost to calcium because, as you can see from the math, alk will rise too much. So a 40 ppm boost to calcium will boost alkalinity by more than 5 dKH. Calcium chloride is the thing to use for such corrections.

zzzdiver · Oct 9, 2015

Following along here, if he used full saturated Kalk it would add about 9ppm ca and 1.27 dKh?

zzzdiver · Oct 9, 2015

Sorry per 1.1 gallon top off

Randy Holmes-Farley · Oct 9, 2015

1.1 gallons of saturated limewater added to 125 gallons of water will boost alkalinity by about 1.0 dKH and about 7.2 ppm calcium.

Jlobes · Oct 9, 2015

this is great info. Since I have done a huge restart/remodel on my tank, I have been thinking about the whole dosing thing. Wondering if I should go the Kalk/ATO route or two part. However, hearing that randy has only used kalk for 20 years, kinda helps me decide what I should be using!

Is it best to just mix the kalk right into the ATO water? or is there some other settling/separating process that needs to happen?

Rjramos · Oct 9, 2015

Following. Batches of Kalk or constant RODI feed into top off reservoir? When and how much do you add more kalk to the ATO reservoir? What about residual cumulative undissolved kalk on the bottom of the reservoir?

Randy Holmes-Farley · Oct 9, 2015

Jlobes said:
this is great info. Since I have done a huge restart/remodel on my tank, I have been thinking about the whole dosing thing. Wondering if I should go the Kalk/ATO route or two part. However, hearing that randy has only used kalk for 20 years, kinda helps me decide what I should be using!

Is it best to just mix the kalk right into the ATO water? or is there some other settling/separating process that needs to happen?

I mix it in a Brute trash can (actually, three plumbed together) and let the solids settle, and pump directly from that container as my ATO.

If you have a smaller reservoir ATO, you can make a large batch, let it settle overnight, and then just use some of it to refill your ATO. Just keep the large batch closed up to prevent air from easily getting to it, and don't stir beyond the initial mixing.

There will be a lot of solids accumulating over time. Most of it is just calcium carbonate, but it may have other stuff that is more often undesirable.

Randy Holmes-Farley · Oct 9, 2015

Rjramos said:
Following. Batches of Kalk or constant RODI feed into top off reservoir? When and how much do you add more kalk to the ATO reservoir? What about residual cumulative undissolved kalk on the bottom of the reservoir?

I reuse it each time as I rarely clean the reservoir. It's been a few years now.

I actually add more than needed, then stir a few minutes while monitoring conductivity to ensure I have adequate potency.

Randy Holmes-Farley · Oct 9, 2015

Jlobes said:
this is great info. Since I have done a huge restart/remodel on my tank, I have been thinking about the whole dosing thing. Wondering if I should go the Kalk/ATO route or two part. However, hearing that randy has only used kalk for 20 years, kinda helps me decide what I should be using!

Is it best to just mix the kalk right into the ATO water? or is there some other settling/separating process that needs to happen?

FWIW, there's nothing wrong with a two part either, but if the tank is not a heavy SPS tank and you have an ATO, I prefer limewater. Even in a heavy SPS tank, I'd probably use limewater plus something else when demand was too high for limewater alone.

This has more on the details of limewater:

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

Jlobes · Oct 9, 2015

Randy Holmes-Farley said:
I mix it in a Brute trash can (actually, three plumbed together) and let the solids settle, and pump directly from that container as my ATO.

If you have a smaller reservoir ATO, you can make a large batch, let it settle overnight, and then just use some of it to refill your ATO. Just keep the large batch closed up to prevent air from easily getting to it, and don't stir beyond the initial mixing.

There will be a lot of solids accumulating over time. Most of it is just calcium carbonate, but it may have other stuff that is more often undesirable.

Thanks for the reply. I will have a small 5-7 gallon ATO, next to the sump. My previous evaporation, before the remodel and new sump, was just about a gallon a day.

So,after mixing and settling a large batch(20 gal), I would fill my ATO, leave the rest in the container with lid. When I fill the ATO next week, of course avoid the settled solids, but what about the surface "crust"? avoid it, stir it in, disturb it as little as possible, while filling the ATO? i apologize for my basic question, but they say the only stupid question is the one you dont ask.

thanks again. so great to have someone with your knowledge and experience, here and active on the forum.

Jlobes · Oct 9, 2015

Randy Holmes-Farley said:
FWIW, there's nothing wrong with a two part either, but if the tank is not a heavy SPS tank and you have an ATO, I prefer limewater. Even in a heavy SPS tank, I'd probably use limewater plus something else when demand was too high for limewater alone.

This has more on the details of limewater:

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

Of course not, nothing wrong with 2 part, but kalk seems so easy and less prone to accidents. Im guessing in a heavy SPS, you'd use limewater with the addition of a Cal supplement?