How to Lower Alkalinity? Is there a Product out there to Lower Alkalinity like you can with PH?

that Reef Guy · Jan 18, 2015

Is there a Product out there to Lower Alkalinity like you can with PH?

In passing I recall somebody telling me there was but I forget what it is called.

I know API makes PH Up and PH Down.

Is there something similar for Alkalinity.

I am setting up a New Frag Tank and the Alkalinity is way to High (13.9).

Reefing Madness · Jan 18, 2015

Muriatic Acid

that Reef Guy · Jan 18, 2015

Reefing Madness said:
Muriatic Acid

Sounds very Dangerous.

Where do you get it?

How much do you Dose?

What I heard about was a Product Made for Aquariums not an Acid.

KoleTang · Jan 18, 2015

pH is the measurement of water acidity. So its easy to add acid or a base to the water to change pH (pH up, pH down).

Alkalinity on the other hand is an indirect method of measuring how much bicarbonate is in the water. As far as I know, it is more difficult to lower this level.

I recommend to let it fall naturally or via water changes using (water with lower alk).

Regarding acid sounding "dangerous". Many minerals, acids, and the like are safe to use in a reef (in the correct manner and dosage) as long as they don't have any other additives.

Triggreef · Jan 18, 2015

Vinegar will lower it but good luck finding any kind of dosage info. GFO will also lower alk and is often overlooked.

Reefing Madness · Jan 18, 2015

The "acidity" (that being essentially negative alkalinity) of muriatic acid straight from the bottle is about 11,000 meq/L.

So adding 1/11,000 of the water volume as this acid will drop alkalinity by 1 meq/l (2.8 dKH).

You want a drop of 13-7 = 6 dKH, or 2.1 times that amount, so you'd add 1/5,100th of the water volume.

13 gallons ~ 49 L

1/5100 of 49 L = 9.6 mL

So I'd add 5 ml and stir well for a few minutes and see what alkalinity you get. Then dose again assuming it seems on the right track.

You'll need to aerate well after adding the acid to blow off the excess CO2 and bring up the pH.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1530419

You can get Muriatic Acid at any pool store, or Walmart.

Randy Holmes-Farley · Jan 18, 2015

The alkalinity lowering of vinegar is temporary until it in metabolized, then it comes back. You need to use a mineral acid such as hydrochloric (=muriatic acid) or sulfuric.

Be careful to not get muriatic acid on yourself and especially not in your eyes.

cwb_reeftank · Feb 1, 2015

would adding that to a tank with a ph of 7.8 be bad?

Reefing Madness · Feb 1, 2015

Yea, thats a bit to low to begin with. You wouldn't be able to use alot all at once, you'd hvae to use quite a bit less, wait for it to come up then use again.

cwb_reeftank · Feb 1, 2015

ok so Id bring up my ph to 8 then add like 1mL maybe? and how would I bring up my ph?

Sangheili · Feb 2, 2015

Seems like a much easier solution is water changes with a NSW-level alk salt.

that Reef Guy · Feb 2, 2015

Sangheili said:
Seems like a much easier solution is water changes with a NSW-level alk salt.

Which Salts do you recommend?

Sangheili · Feb 2, 2015

Tropic Marin Pro Reef or Red Sea blue bucket.

UK_Pete · Feb 2, 2015

If you do want to use the acid, raise the pH first by blowing off the CO2 in the tank (thats whats lowering the pH). So open the windows and let the tank breath fresh air for a few hours, including through the skimmer. You should find pH rises. Then you can add acid very carefully, using Reefind madness maths above.

Randy Holmes-Farley · Feb 2, 2015

How to Lower Alkalinity? Is there a Product out there to Lower Alkalinity lik...

A Much better plan than adding acid to the display is to add the muriatic acid to new salt water, to get to an alk of, say, 6-7 dKH, fully aerate it to bring the pH back to a reasonable range, then use it for your regular water changes.

Or use a lower alk salt.