Having trouble keeping alk stable - help

[sanzz18]

My alk seems to be bouncing between 9-10dkh when my goal is around 8-8.5. I made a post about alk rising on it’s own so understand a little about reasons why that is happening.

-not dosing anything that adds alk
-no calcium reactor
-haven’t been doing any water changes l
-slowly dosing elimiphos via ATO to slowly lower po4 to 0.15ish from close to 0.4
-recently dosed mag to almost 1400 from just under 1300
-Nitrates are around 35, going to be lowering them via waterchanges once my airstone comes in and pick up muriatic acid for NSW (to slowly start lowering alk via water changes)
-only coral in my tank at the moment is gsp (been trying to keep really cheap acros multiple times and they always STN)
-my tank is now 2 years old

So without chasing numbers I am trying to get all my parameters stable so I can try SPS again. My only challenging parameter I would say is alkalinity. Given everything I stated, how do I keep my alk stable and not fluctuating so I can keep SPS?

 

[branbray07]

Could you please give information about your system. Tank volume, filtration, lighting, equipment, dosing/feeding.

 

[sanzz18]

Could you please give information about your system. Tank volume, filtration, lighting, equipment, dosing/feeding.

No dosing besides elimiphos, water volume is about 180g, have a skimmer (regal 200int), chaeto in refugium, t5/radion xr15 hybrid fixture with about 300-350 par at top of rocks, and feed mysis/rods/nori.

 

[TokenReefer]

What was your other post?

 

[sanzz18]

What was your other post?

It was about my alk rising all by itself without dosing or waterchanges. That post was awhile back. Basically I am just trying to get my alk to more or less stay put. Reduce these random swings.

 

[Randy Holmes-Farley Verified Community Expert]

Falling nitrate will raise alk, but it can also rise slowly for other reasons, and that only becomes apparent when alk demand is very low.

What salt mix are you using now and have you measured the alk in it?

 

[sanzz18]

Falling nitrate will raise alk, but it can also rise slowly for other reasons, and that only becomes apparent when alk demand is very low.

What salt mix are you using now and have you measured the alk in it?

I will double check my nitrates but they have recently gone from 30 to about 35 so they are not even falling. My alk demand is definitely super low, it even seems like my coraline has significantly slowed down might have been because of low mag under 1300?

I am using Red Sea blue bucket and never seen it measure higher then 9dkh, although once again, I have not done waterchanges in recent weeks. Going to do them as soon as my airstone comes in and I pick up muriatic acid.

 

[Randy Holmes-Farley Verified Community Expert]

I'd personally just keep watching it longer and see what happens. 9 dKH is fine and not at the upper limit of fine.

 

[sanzz18]

I'd personally just keep watching it longer and see what happens. 9 dKH is fine and not at the upper limit of fine.

Well the problem is its actually heading back up to 10. I always read that closer to 7-8dkh gives you more room for error?

 

[Randy Holmes-Farley Verified Community Expert]

Well the problem is its actually heading back up to 10. I always read that closer to 7-8dkh gives you more room for error?

My recommended alk range is 7-11 dKH.

Hard corals grow faster at the high end, but you do want to have sufficient N and P when having high alk or certain SPS coral may get burnt tips, likely from the skeleton growing faster than the tissue can keep up.

 

[sanzz18]

My recommended alk range is 7-11 dKH.

Hard corals grow faster at the high end, but you do want to have sufficient N and P when having high alk or certain SPS coral may get burnt tips, likely from the skeleton growing faster than the tissue can keep up.

Then I don’t understand for the life of me why I cannot keep easy acropora or montis. They all STN and been through it all researching why. The only thing I can think of is high nutrients. With an alk of 9-10 where would you want your N&P to hang around?

 

[Randy Holmes-Farley Verified Community Expert]

Then I don’t understand for the life of me why I cannot keep easy acropora or montis. They all STN and been through it all researching why. The only thing I can think of is high nutrients. With an alk of 9-10 where would you want your N&P to hang around?

5-10 ppm nitrate and 0.05 ppm phosphate should be sufficient to prevent any "low nutrient" problems from alk in the 7-11 dKH range, IMO.

 

[sanzz18]

5-10 ppm nitrate and 0.05 ppm phosphate should be sufficient to prevent any "low nutrient" problems from alk in the 7-11 dKH range, IMO.

Okay perfect, so obviously it will take 4-5 25% waterchanges to get the nitrates to 10 or under. Should I lower the alk on that salt mix or not mess with the alk too much?

Thanks for all the help by the way, you answer quite a bit of my posts.