High Alk

marvelousone · Feb 17, 2018

My tank has been 8.9 to 9.0 Dkh using Hannah tester. My alk jumped up to 9.4Dkh. I was going to do a water change. I tested the new water and it is 11.1 Dkh. I use instant ocean which I thought was lower than that. So my question is, Can I do something to the new water to get the alk lower.

Randy Holmes-Farley · Feb 17, 2018

marvelousone said:
My tank has been 8.9 to 9.0 Dkh using Hannah tester. My alk jumped up to 9.4Dkh. I was going to do a water change. I tested the new water and it is 11.1 Dkh. I use instant ocean which I thought was lower than that. So my question is, Can I do something to the new water to get the alk lower.

Just let it drop on its own, assuming you have some consumption.

Instant Ocean (both types, regular and Reef Crystals) are high alk mixes.

marvelousone · Feb 17, 2018

Randy Holmes-Farley said:
Just let it drop on its own, assuming you have some consumption.

Instant Ocean (both types, regular and Reef Crystals) are high alk mixes.

I can let it drop in the tank but should I go ahead and do water change. I will be changing salt mixes.

Randy Holmes-Farley · Feb 18, 2018

I wouldn't. Water changes are not a great way to adjust alkalinity.

marvelousone · Feb 18, 2018

Randy have you heard of using Mauriac acid to lower alk in the new mixed water.

Randy Holmes-Farley · Feb 18, 2018

marvelousone said:
Randy have you heard of using Mauriac acid to lower alk in the new mixed water.

Sure. I think I may have been among the originators of the method as reefers use it.

It is a fine way to lower alk, but the pH drops really low and generally isn't recommended in a display tank unless you do it very slowly. Most of the time, folks use it on new salt water.

Randy Holmes-Farley · Feb 18, 2018

Are you really concerned that a tank that was often at 9 dKH is going to suffer at 9.4 dKH? Is it seeming to suffer?

marvelousone · Feb 18, 2018

Randy Holmes-Farley said:
Are you really concerned that a tank that was often at 9 dKH is going to suffer at 9.4 dKH? Is it seeming to suffer?

No I am concerned of 11.1 on my new water. I would like to do a water change but don't want my alk to raise more than it is now. Is Mauriac acid the same acid to use in cooking live rock.

Randy Holmes-Farley · Feb 18, 2018

marvelousone said:
No I am concerned of 11.1 on my new water. I would like to do a water change but don't want my alk to raise more than it is now. Is Mauriac acid the same acid to use in cooking live rock.

Ah, yes, treating the new water is a fine plan. Just aerate well after treatment before use.

Yes, muriatic acid is the same acid used to treat dead rock to remove phosphate, copper, etc, that may be on the surface. You use far, far more in that application.

marvelousone · Feb 18, 2018

So in 20 gals of fresh saltwater in a brute can how much acid do I dose.

Randy Holmes-Farley · Feb 18, 2018

Here's a thread on it:

https://www.reef2reef.com/threads/changing-salt-to-have-lower-alk.336827/

marvelousone · Feb 18, 2018

Thank you

Randy Holmes-Farley · Feb 18, 2018

You're welcome.

Happy reefing.

marvelousone · Feb 19, 2018

I am a lost. I woke up this morning and my alk was 9.8. It is raising and all I dosed was nopo-x to lower nitrates. I have fresh water to do water change but it was at 11.1. I added Seachem acid buffer last night to lower the alk. It lowered it to 9.5 so I dosed again to get it around 8. I will do water change maybe tomorrow. When is my alk going up.

My levels are
alk 9.8
calc. 410
mg 1260
no3 4
po4 .04