How do I lower alkalinity to newly mixed salt, before adding to display

[mta_morrow]

I guess the title says it all.

My tank seems really happy with alk around 7.8-8.2. lets call it 8.

My Brightwell salt, which I still have a lot of, mixes around 10.5.

I mix 28 gallons at a time. 20 for WC, and I fill 8, 1 gallon jugs for whatever its needed for.

Every time I do a WC, alk goes up quickly and it irritates things.

is there anything I can do to lower the alk to 8 while mixing?

Thanks

Mike

 

[cracker]

good question I'd like to know as well.

 

[Scotty Buttons]

I think ive herd using muriatic acid will lower it but let's wait for a expert to chime in.

 

[chipmunkofdoom2]

You can use hydrochloric acid, but you'll need to use caution because of the strength of the solution and the fumes.

For example, let's say you have a ~35% HCl solution (often sold as muriatic acid at hardware stores, or 12M from scientific suppliers). About 0.123 mL of this acid will reduce the alkalinity of 1 gallon of saltwater by about 1 dKh.

If you need to reduce 28 gallons by 2 dKh, that's 28 gallons * 0.123 mL/gallon * 2 dKh reduction = about 6.88 mL of acid.

I'll defer to Randy to check my math of course but those are the basics. In addition to wearing safety equipment (gloves and goggles at the very least), be sure to aerate the water for at least 24 hours after adding the acid. The addition of HCl produces a lot of CO2, which lowers pH. This needs to be driven out of the water by aerating before you can use it.

 

[MTBake]

I use muriatic acid to drive down the alk in my new water. I use Tropic Marin salt and it mixes to 9.3dkh. I want my tank at 7dkh. Adding 3.2ml or muriatic acid per 5 gallons drives my alk from 9.3 to 6. I'm still bringing my alk down from 9.3 to 7. I'm at 7.8 currently and figure a couple more water changes will get me close enough.

Adding muriatic acid will lower the ph as well. You will need to aerate the water for 24 hrs before your water change to bring the ph back up. I use an air pump and stone in my mixing container to accomplish this. I add the acid once the salt has mixed clear.

 

[gonzo620]

I don’t really ever adjust water change water. I have a 180 gallon so water dilution is plus for me. But it would seem the logical long term solution would be to consider a different salt. One that mixes closer to your desired parameters. My 2c

 

[mta_morrow]

You can use hydrochloric acid, but you'll need to use caution because of the strength of the solution and the fumes.

For example, let's say you have a ~35% HCl solution (often sold as muriatic acid at hardware stores, or 12M from scientific suppliers). About 0.123 mL of this acid will reduce the alkalinity of 1 gallon of saltwater by about 1 dKh.

If you need to reduce 28 gallons by 2 dKh, that's 28 gallons * 0.123 mL/gallon * 2 dKh reduction = about 6.88 mL of acid.

I'll defer to Randy to check my math of course but those are the basics. In addition to wearing safety equipment (gloves and goggles at the very least), be sure to aerate the water for at least 24 hours after adding the acid. The addition of HCl produces a lot of CO2, which lowers pH. This needs to be driven out of the water by aerating before you can use it.

Thanks for the detailed response. Seems easy enough to do and doesn’t scare me so that’s a plus!

This may very well be the the way I go.

 

[mta_morrow]

I use muriatic acid to drive down the alk in my new water. I use Tropic Marin salt and it mixes to 9.3dkh. I want my tank at 7dkh. Adding 3.2ml or muriatic acid per 5 gallons drives my alk from 9.3 to 6. I'm still bringing my alk down from 9.3 to 7. I'm at 7.8 currently and figure a couple more water changes will get me close enough.

Adding muriatic acid will lower the ph as well. You will need to aerate the water for 24 hrs before your water change to bring the ph back up. I use an air pump and stone in my mixing container to accomplish this. I add the acid once the salt has mixed clear.

Thanks for the reply and explanation!

 

[mta_morrow]

I don’t really ever adjust water change water. I have a 180 gallon so water dilution is plus for me. But it would seem the logical long term solution would be to consider a different salt. One that mixes closer to your desired parameters. My 2c

I do plan on changing salts after I use what I have.

Which is a lot!

If my tank stays happy through this, I may just continue doing it.

Thanks for the reply!

 

[MTBake]

Do be careful with this stuff. Gloves and goggles would not be a bad idea. It is acid after all

 

[UCF Alum]

I use tropic Marin pro reef, although my corals just don’t seem to care for it. The bucket I purchased two months ago mixed at 7.5 dKh. I just recently switched over to Red Sea. I used to use the Red Sea pro salt but the alkalinity was too high. The batch of regular Red Sea salt mixes at 8.1.

Remember you can always raise alkalinity by dosing. What you can’t do is lower it unless you mess with muriatic acid, which is something I do not want to do.

 

[Bmasculine]

I’ve also used muriatic acid to bring down alk in fresh batches of sw with no ill effects. I have since switched to a salt that mixes closer to my tank params. I actually learned this from my brother whom owns a pool company. You will want to check your ph before using.

 

[Frogger]

I add 2 part and on the day I am changing the water I don't add the alkalinity portion and re-correct at the end of the day. Saves having to add muriatic acid.

It seems most salt mixes mix high alkalinity.

 

[Waters]

Rather than worrying about lowering the ALK, I would change salt to something that mixes to a lower ALK, like Red Sea Blue.

 

[mta_morrow]

Rather than worrying about lowering the ALK, I would change salt to something that mixes to a lower ALK, like Red Sea Blue.

Per my posts above, that’s the plan after I use the salt I have[emoji57]

 

[Waters]

Per my posts above, that’s the plan after I use the salt I have[emoji57]

Sorry lol....that is what happens when you quickly skim through posts while at work

 

[mta_morrow]

Sorry lol....that is what happens when you quickly skim through posts while at work

[emoji6]

 

[Randy Holmes-Farley Verified Community Expert]

Lowering alk is easy, very cheap, and you can use nontoxic materials such as sodium bisulfate solid if the liquid muriatic acid scares you.

 

[mta_morrow]

Lowering alk is easy, very cheap, and you can use nontoxic materials such as sodium bisulfate solid if the liquid muriatic acid scares you.

Thanks for chiming I’m on this. I appreciate it. I’m cool with using muriatic acid and the formula provided by chipmunkofdoom seems easy enough to follow.

 

[mic209]

Have you tried mixing to a lower salinity? When I was using reef crystals, I would mix it to 1.024-1.025 so the ALK was lower. Although it still didn’t mix up low enough to what I kept my tank at so the better solution (as mentioned already) was to switch salts. I went with fritz RPM and never saw ALK over 8.5DKH. Sometimes it would mix up on the low side(6-7dkh), but it’s much easier to raise with a little 2 part than it is to bring it down.