Low Alk - Asking for help.

patrck17

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Hello,

I have a 150g display with a 25g or so sump. Water looks good. First tank so I really don't have much experience with corals. I have mostly soft corals. They open up and seem to be healthy. I also have a hammer, and frogspawn and duncan. Which all seem to be doing okay, but I wouldn't say they are thriving. The duncan appears to be struggling. I've had the tank set up here for a few months and I was mostly trying to work on bringing up my refugium and lowering nitrate and phos. Admittedly I sort of neglected other parameters and have been using the ORP, PH, and Salinity probes to sort of eyeball the water for the last few weeks.

Today I've been trying to make a push to get the tank into a good rhythm and I started water measurements with Salinity then Alk.

Hanna:
Salinity: 1.025
Alk 2.8

Apex measurements
ORP: 375
PH: 7.71

This is as far as I got so far. I am going to spend some time cleaning up some wiring and wanted to make this post now to see if anyone can chime in early. I know the questions will be about other water parameters, and I will collect those shortly, but for now my question is about ALK.

Specifically with it this low is there a quick way to snap it back into the green, or do I need to spend a few days or weeks to get it back to where it needs to be? Specifically asking for recommendations for a treatment plan. I have BRS's alk/calc 2 part on hand and I have dosing pumps I can set up. But for now I am curious about just getting it back where it needs to be asap.

More to come, thanks for the help.

IMG_8292.jpeg IMG_8291.jpeg
 

lapin

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2.8 = 7.8. It is a bit low.
I recommend Randy’s baked baking soda for starters. It’s easy and in your case I would only add the alk part. No need for any fancy dosing pump until you get it up to where you need it.
 
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patrck17

patrck17

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Looked through my stuff and I have Seachem Carbonate, lol. But glad I posted this because the soda ash recipe linked works fine as well.
 
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patrck17

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2.8 = 7.8. It is a bit low.
I recommend Randy’s baked baking soda for starters. It’s easy and in your case I would only add the alk part. No need for any fancy dosing pump until you get it up to where you need it.


Sorry, I don't follow what you mean when you say 2.8 = 7.8. I thought this may have been a typo. The Hanna reads dKH and it says 2.8. That would suggest very low to me? Just want to make sure I am not missing something before I dose 6-7 dKH over the next week or two.
 

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@Randy Holmes-Farley do you have a minute to help the OP please?

Sorry, I don't follow what you mean when you say 2.8 = 7.8. I thought this may have been a typo. The Hanna reads dKH and it says 2.8. That would suggest very low to me? Just want to make sure I am not missing something before I dose 6-7 dKH over the next week or two.

Your Alk test of 2.8 dKH is almost certainly an error with your test kit or your testing procedure. I would test again, or consider bringing a sample to your Local Fish Store and ask them to test the water. Very low Alk is like 5.5 to 6.0 dKH, I don't believe your 2.8 dKH result if you're using any of the popular salt mixes.

What salt mix are you using, and have you tried testing the Alk of newly mixed saltwater?
 

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And your tank looks very good! If your Alk is really 2.8 dKH, your corals would be giving up the ghost 👻

I think even the poor fish would be flopping at 2.8 dKH 🙃
 
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I am using Instant Ocean, Reef Crystals. The one in the orange box. I checked three times and was 2.8 each time, but that is the type if info I was looking for. I'll go back and check instructions and ensure I am not doing it wrong. Then try to get another method to take the measurement or use a reasonable control.
 

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I am using Instant Ocean, Reef Crystals. The one in the orange box. I checked three times and was 2.8 each time, but that is the type if info I was looking for. I'll go back and check instructions and ensure I am not doing it wrong. Then try to get another method to take the measurement or use a reasonable control.
Something is wrong with your testing I'm quite sure. Don't make any adjustments to your system until you verify your Alk testing. Hopefully, RHF will see my tag above and will weigh in here and help us all out 🙂
 
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patrck17

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Something is wrong with your testing I'm quite sure. Don't make any adjustments to your system until you verify your Alk testing. Hopefully, RHF will see my tag above and will weigh in here and help us all out 🙂

I added ~24g of baking soda that I baked out for little over an hour at 350F. Added about 45 mins ago. Just performed the test again and it increased to 4.3 dKH. So if anything the meter is increasing properly, but may still be offset or just not scaling properly.

Either way I won't be doing anything else until I can confirm the measurements. I'll grab a sample and take it to the fish store tomorrow. Thanks!
 

Fish Fan

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I added ~24g of baking soda that I baked out for little over an hour at 350F. Added about 45 mins ago. Just performed the test again and it increased to 4.3 dKH. So if anything the meter is increasing properly, but may still be offset or just not scaling properly.

Either way I won't be doing anything else until I can confirm the measurements. I'll grab a sample and take it to the fish store tomorrow. Thanks!
No need to thank me 🙃

I wouldn't make any more changes until @Randy Holmes-Farley sees this.

Many here at R2R run Reef Crystals, and I believe it mixes to a fairly high Alk like ~9.0-10 dKH. That means that the water going in to your tank is ~9.0-10 dKH and though your tan looks great, nothing in your tank is dropping the Alk that much, I don't think it's even possible.
 

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patrck17

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Hold up - is this what you've been using for testing all along?
No, I am using a Hanna Alk tester. That is the only other test I have on hand that measures Alk. I use them to sort of eyeball where I am. I posted it as a second reference point.
 

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The HannaChecker for Alkalinity is great but the reagent expires rather quickly and shows extremely low readings. You probably need to buy a new reagent. Please double check, but you should need the HI772-26 reagent.

If you are still worried that the readings might be off, you can double check with the HI772-11 calibration standard, which will tell you if the photometer is still fine.
 

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The HannaChecker for Alkalinity is great but the reagent expires rather quickly and shows extremely low readings. You probably need to buy a new reagent. Please double check, but you should need the HI772-26 reagent.

If you are still worried that the readings might be off, you can double check with the HI772-11 calibration standard, which will tell you if the photometer is still fine.
I agree with everything. No chance your alk is that low especially with reef crystals, mixes like high than 10. Unless you let it dwindle down last like 2 months. Hanna alk checkers are notorious for not being accurate at time especially when regiment expires. I stopped using and just use salifert now. I would buy another regiment and even another accurate test kit, salifert, Red Sea to make sure it’s your tester
 
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Thanks everyone. I bought more reagent and a salifert test kit. I’ll check again once they arrive.
 
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patrck17

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Quick follow up to everyone. You guys were right the test was off. I got new reagent and the Salifert test and they match at ~ 9dKH. I'll start to log these and get a handle on depletion rate moving forward.
 

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Quick follow up to everyone. You guys were right the test was off. I got new reagent and the Salifert test and they match at ~ 9dKH. I'll start to log these and get a handle on depletion rate moving forward.
Great to see! Good luck going forward!
 

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