How do I lower Alkalinity?

[LonitzCMU]

My current parameters are:

Ammonia: 0
Nitrtite: 0
Nitrate: 0
Phosphate: .25
Calcium: 360 PPM (Dosing today to raise to 410, then tomorrow to 440)
dKH: 14

I want to get my alkalinity down to 9 where BRS recommended. Can anyone tell me how to do that? Also, anything else I should be concerned about with these numbers?

 

[Tiki Reef Joshua]

You will hear different opinions but I’d bump that nitrate up to a measurable level.

 

[Fishurama]

If you want to go the natural route, 20-25 percent water change weekly , no dosing, and you should get right around where you want to be in 2-3 weeks. Or White vinegar. So its slow and steady vs speed. The Choice is yours

EDIT: Also as another poster said, get your nitrates up a little. 0 despite what you would think is not good.

 

[tvan]

Muriatic acid, seachem acid buffer....
Both of these will drop your ph as well...

 

[Randy Holmes-Farley Verified Community Expert]

If you want to go the natural route, 20-25 percent water change weekly , no dosing, and you should get right around where you want to be in 2-3 weeks. Or White vinegar. So its slow and steady vs speed. The Choice is yours

EDIT: Also as another poster said, get your nitrates up a little. 0 despite what you would think is not good.

That, obviously, only works if you use a very low alk salt mix. With IO, it will never get there.

With a salt mix at 7 dKH, this is what consequtive 25% changes do:

14
12.3
10.9
10.0
9.2
8.7
8.2

 

[ThePickeledReef]

Do you have any ideas on how it got to 14dhk??

 

[Rickybobby]

I bought a bag of io reef salt and my dkh went sky high as well lost a couple corals during this period. I changed salt mixes and am working on getting mine back down

 

[ThePickeledReef]

I bought a bag of io reef salt and my dkh went sky high as well lost a couple corals during this period. I changed salt mixes and am working on getting mine back down

Even unmixed Instant ocean Salt shouldn’t get you to 14 dkh. Just think have to identify what got it that high before trying to solve it.

 

[DivingTheWorld]

With Alk at 14, I’m going to guess you’re using one of the many high Alk “reef” salts. If so, as Randy pointed out, doing standard water changes isn’t going to help.

If you’re not dosing and this is due as I suspect to high Alk salt, you have two options.

Option 1: Start using a low Alk salt like Red Sea blue bucket and do gradual water changes until it’s where you want.

Option 2: Use muriatic acid to drop the Alk in your water change water, then do gradual water changes until it’s where you want.

Note: DO NOT dose muriatic acid directly in your display tank. It will cause your pH to plummet. Dose in your WC mixing container and give it 1-2 days to allow the pH to get back to normal. Adding an air stone helps speed it up.

 

[Fishurama]

That, obviously, only works if you use a very low alk salt mix. With IO, it will never get there.

With a salt mix at 7 dKH, this is what consequtive 25% changes do:

14
12.3
10.9
10.0
9.2
8.7
8.2

Thats guesswork. You can't guess how much alk will be absorbed into live rock or dissipate,etc then on top a water change. Also it doesn't matter what salt you use... White vinegar works...

 

[homer1475]

Thats guesswork. You can't guess how much alk will be absorbed into live rock or dissipate,etc then on top a water change. Also it doesn't matter what salt you use... White vinegar works...

All I'm going to say, this is completely wrong. @Randy Holmes-Farley is spot on as usual.

And many people dose vinegar(yes plain old white vinegar to feed bacteria), including myself, yet none report a sudden drop in ALK.

 

[Fishurama]

All I'm going to say, this is completely wrong. @Randy Holmes-Farley is spot on as usual.

And many people dose vinegar(yes plain old white vinegar to feed bacteria), including myself, yet none report a sudden drop in ALK.

And im going to say you are completely wrong since you are guessing for someones ambient temps, rockwork, flow, tank temp,etc which all contribute to alk depletion and are guessing. If you knew more of OPs set up you could make an educated guesstimate, but knowing none of these factors, to take a wild guess is wrong.

 

[homer1475]

I don't know I've been running a marine tank for the better part of 20 years, and have never seen temp, flow, or the amount of rock(unless it was dead dry rock and the tank was brand new) deplete alkalinity.

But I won't argue, I'll let @Randy Holmes-Farley explain it better.

 

[ThePickeledReef]

Easy folks.
Still need to address why it’s 14DKh to start with even red see coral pro salt mix is 12.5.

 

[homer1475]

I saw above the OP used a "Reef" salt, some mix up this high.

Until the OP chimes back in on what salt he's using, we can only guess.

I've seen RC mix continuously very close to 14DKH.

 

[One Reefing Boi]

All I'm going to say, this is completely wrong. @Randy Holmes-Farley is spot on as usual.

And many people dose vinegar(yes plain old white vinegar to feed bacteria), including myself, yet none report a sudden drop in ALK.

what in the vinegar does the bacteria feed on? what bacteria is eating it?

 

[homer1475]

Vinegar is a carbon source, same as vodka, or sugar(DIY NOPOX is vodka, and vinegar). Your feeding bacteria that consume nitrates and phosphates, you then remove them by wet skimming.

Read up on carbon dosing for a more detailed explanation.

 

[One Reefing Boi]

Vinegar is a carbon source, same as vodka, or sugar(DIY NOPOX is vodka, and vinegar). Your feeding bacteria that consume nitrates and phosphates, you then remove them by wet skimming.

Read up on carbon dosing for a more detailed explanation.

ah ok, thanks! ill look into it. I don't run a skimmer nor have an issue with it but never hurts to know about it!

 

[blasterman]

Just test the darn salt mix freshly mixed and see if it's the problem. {bangs head against wall}

Reef Crystals can mix as high as 12-13dKH. I've had bags of coralife test as high as 15dKH. Instant Oceas is around 9.5

I've used muriatic acid (hydrochloric acid) to lower dKH after dosing pump snafus and it works fine . In small amounts (no more than 1ml per 10 gal) along with aggressive aeration.

 

[Randy Holmes-Farley Verified Community Expert]

Thats guesswork. You can't guess how much alk will be absorbed into live rock or dissipate,etc then on top a water change. Also it doesn't matter what salt you use...

It is the exact and precise effect of a water change.

There obviously are other effects that may make alk decline, which I am not guessing about. Since his alk is already high and staying high, these effects are minor, at best, however.

i think you may misunderstand alkalinity if you apply words like dissipate.

Also it doesn't matter what salt you use...

That is just so wrong. How could it not matter? Water change alk at 7 dKH vs 12 dKH? Makes an obvious and huge difference.

.. White vinegar works...

Not true.

Vinegar will result in no long term lowering of alkalinity. As soon as it is metabolized, the alk returns.