How to lower alk?

Pete polyp · Jun 21, 2014

My 40 has been up and running for a few months now getting ready for the sps. I checked alk today and it was 14.5. I really have no clue how it got so high. No dosing other than kalk in the topoff. With no corals in the tank how in the world can I get that number down other than water changes? I changed 15 gallons and it went down to 13.2. Am I going to have to throw some lps in there to bring it down or what?

ritter6788 · Jun 22, 2014

What salt are you using?

I'd start by taking the kalk offline.

Pete polyp · Jun 22, 2014

I took it offline today, and haven't dosed any kalk in 2 weeks. The kalk reactor has been empty and just rodi ran through it for topoff. I'm using io for salt. It baffles me to how it got this high. Maybe it was a result of using paraguard?

ritter6788 · Jun 22, 2014

IO alk is a bit high (for me) to begin with so maybe that and the kalk with no coral to use up the alk raised it too high. I'd just let it fall on it's own.

Pete polyp · Jun 22, 2014

How's it going to fall on its own with no corals? Io mixes up a bit high for my liking also (10). This makes me wish they made salt mix with 0 everything and sold the elements separately.

rako1 · Jun 22, 2014

what is your cal

Pete polyp · Jun 22, 2014

Pete polyp · Jun 22, 2014

Well, it was before the water change

ritter6788 · Jun 22, 2014

Pete polyp said:
How's it going to fall on its own with no corals? .

Coralline algae.

Pete polyp · Jun 22, 2014

ritter6788 said:
Coralline algae.

Really no growth yet. Seems like it would take a pretty good while for coralline to drop the alk 4 dkh

mcarroll · Jun 22, 2014

It will go down naturally over time due to miscellaneous biological processes, but not very fast. Water changes will help. Definitely do NO DOSING.

Thankfully, there's nothing wrong with alk temporarily being that high. It's not fashionable, but several folks have successfully run stony coral tanks purposefully in that alk range.

BTW, the slight boost in IO's alk vs NSW is just to account for the use of the "miscellaneous processes" during the average time between water changes. Tiny. If you used water that had NSW numbers for water changes, eventually (would take a while, as noted) your alk would tank and you may start seeing wicked pH swings...bad even for a fish only tank.

BTW, I'm confused...were you running the reactor with powder in it even though you had no stony corals? If so, why? This is the whole reason your alk spiked. Just let it ride out and don't do anything drastic to "fix it".

-Matt

Pete polyp · Jun 22, 2014

I was using a kalk reactor to keep the parameters where they were. I really thought all my sps would have been in there long ago. One setback after another and here I am a couple months later. The whole concept behind kalk is not to increase calcium or alkalinity, but to help keep them where they're at. I know sps can be kept with high alk like this, but they're coming from a tank that has been stable at 8.3-8.6. So that could be a pretty big problem. I'm thinking of dumping a dozen acan in there to help bring it down more. I plan on doing more water changes in the next week to bring it down more. I was just wondering if there is anything I could use to drop it down besides time and water changes.

rako1 · Jun 22, 2014

Bring up your cal and it will use up your alk and produce some nice corline it will take a little thime though

rako1 · Jun 22, 2014

But remember you want evrything slow in this hobby

Pete polyp · Jun 22, 2014

I'm not too worried about having patience right now. The tank has no corals right now.

Reef_a_holiks · Jun 22, 2014

i believe adding calcium only will bring down alkilinity , and put it back to a balanced ratio

Pete polyp · Jun 22, 2014

I changed water today and brought it down to 10. Hopefully in the next few weeks it will drop to my target of 9.

Reefing Madness · Jun 23, 2014

You can knock it down using Muriatic Acid if its still not in your range.
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.
"Randy Farley-Holmes"

NanaReefer · Jun 23, 2014

mcarroll said:
It will go down naturally over time due to miscellaneous biological processes, but not very fast. Water changes will help. Definitely do NO DOSING.

Thankfully, there's nothing wrong with alk temporarily being that high. It's not fashionable, but several folks have successfully run stony coral tanks purposefully in that alk range.

BTW, the slight boost in IO's alk vs NSW is just to account for the use of the "miscellaneous processes" during the average time between water changes. Tiny. If you used water that had NSW numbers for water changes, eventually (would take a while, as noted) your alk would tank and you may start seeing wicked pH swings...bad even for a fish only tank.

BTW, I'm confused...were you running the reactor with powder in it even though you had no stony corals? If so, why? This is the whole reason your alk spiked. Just let it ride out and don't do anything drastic to "fix it".

-Matt

Wonderful advice!!

NanaReefer · Jun 23, 2014

Reefing Madness said:
You can knock it down using Muriatic Acid if its still not in your range.
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.
"Randy Farley-Holmes"