Need some assistance with High KH

[kermitdafrog]

Hello Everyone,

I have a JBJ 45 Rimless AIO and it was taken over by someone else that was running it for a long time. It's been running for the last 3 months with a Protein Skimmer. Having an issue with my numbers and don't know which direction to take. I have lost a couple fish and corals as I think the parameters at that time were way off. I have just recently bought the Apex EL so I can do some properly monitoring.

I have been doing a weekly 10% Water Change.

PH - 77.3-78-1
Sal - 1.024
KH -16.1
CAL - 426
NO3 - Haven't gotten a good read that i'm comfortable to call it.

Your insight would be greatly appreciated.

 

[GabeM]

What salt are you using and are you dosing anything?

Also what test kit and how many tests have you run?

 

[kermitdafrog]

What salt are you using and are you dosing anything?

Also what test kit and how many tests have you run?

AS for the Salt I don't know currently I have been going to the person I got the tank from opened up a store. So it's what he is mixing I will ask tho. I will soon be getting a bucket of salt and mixing it at home once a shipment comes in.
Dosing - No that's the next thing I need to start but don't know when to start.

Test kits Apex - TEMP/PH
Hanna- CAL/KH
I have an API that I was testing everything else with.

 

[GabeM]

AS for the Salt I don't know currently I have been going to the person I got the tank from opened up a store. So it's what he is mixing I will ask tho. I will soon be getting a bucket of salt and mixing it at home once a shipment comes in.
Dosing - No that's the next thing I need to start but don't know when to start.

Test kits Apex - TEMP/PH
Hanna- CAL/KH
I have an API that I was testing everything else with.

Don't start dosing until you have your dkh issue sorted out. Do you have any water from the store you can test? I would test that as a next step.

 

[kermitdafrog]

Don't start dosing until you have your dkh issue sorted out. Do you have any water from the store you can test? I would test that as a next step.

No I don't I used it all yesterday on the water change. I will go tomorrow and get some more and will test it before I do another water change.

And I forgot to answer. I have been testing daily to see the changes and charting it.

 

[chipmunkofdoom2]

First, I would confirm your test results are correct. It's not impossible to have alkalinity of 16.1 dKh, but it's unusual, especially if you're not dosing any supplements. If that is your actual alkalinity, I would test some newly mixed saltwater to make sure it doesn't have sky-high alkalinity. I would also calibrate your salinity measurement tool to ensure that your salinity isn't too high, which can increase these numbers.

If all that checks out, you have a few options to reduce alkalinity. You can 1) do nothing and allow it to decline slowly over time, 2) perform water changes with a lower alkalinity salt like Red Sea's blue bucket, or 3) dose HCl to reduce the alkalinity instantly.

I would not recommend solution #3. It's easy to get wrong and HCl is dangerous to work with if you don't know what you're doing.

I would probably choose solution #1. Alkalinity will decline over time as carbonate is used by corals or precipitates abiotically.

Solution #2 is also an option if you'd like more immediate results, although this will still take some time. Let's assume you do 25% water changes every week and you use Red Sea's blue bucket salt, which should have an alkalinity around 8 dKh. After 4 weeks, your alkalinity will be around 10.7. This assumes you have no abiotic precipitation and you don't add any alkalinity.

 

[kermitdafrog]

First, I would confirm your test results are correct. It's not impossible to have alkalinity of 16.1 dKh, but it's unusual, especially if you're not dosing any supplements. If that is your actual alkalinity, I would test some newly mixed saltwater to make sure it doesn't have sky-high alkalinity. I would also calibrate your salinity measurement tool to ensure that your salinity isn't too high, which can increase these numbers.

If all that checks out, you have a few options to reduce alkalinity. You can 1) do nothing and allow it to decline slowly over time, 2) perform water changes with a lower alkalinity salt like Red Sea's blue bucket, or 3) dose HCl to reduce the alkalinity instantly.

I would not recommend solution #3. It's easy to get wrong and HCl is dangerous to work with if you don't know what you're doing.

I would probably choose solution #1. Alkalinity will decline over time as carbonate is used by corals or precipitates abiotically.

Solution #2 is also an option if you'd like more immediate results, although this will still take some time. Let's assume you do 25% water changes every week and you use Red Sea's blue bucket salt, which should have an alkalinity around 8 dKh. After 4 weeks, your alkalinity will be around 10.7. This assumes you have no abiotic precipitation and you don't add any alkalinity.

Just got back from the shop with 2 buckets of fresh salt water. I also borrowed their Hanna checker to make sure. Was able to check the mix water at 6.7 dkh. So I was able to confirm that it's not their salt water and then when I checked mine it was again at 16.1 dkh. Tonight I will do a 20% water change and see what that does to the tank.

 

[chipmunkofdoom2]

Tonight I will do a 20% water change and see what that does to the tank.

You should end up with around 14.2 dKh.

 

[kermitdafrog]

You should end up with around 14.2 dKh.

Would tonight be to soon to do a 20% water change if I did it on Monday?

 

[chipmunkofdoom2]

Would tonight be to soon to do a 20% water change if I did it on Monday?

Too soon in what way? There shouldn't be any harmful effects caused doing another water change tonight.

The only thing you may want to consider is doing smaller water changes at first, maybe 10%. Because the new water's alkalinity is so low compared to your tank, a 20% change would drop your alkalinity by almost two full dKh. A 10% change would drop your alkalinity by about 1 dKh.

After a few 10% changes, it might make sense to move up to 20% changes to continue getting significant reductions from your water changes.

I would also still encourage you to find out how your alkalinity got so high in the first place. Water changes will solve your problem for now, but it will not prevent it from happening again in the future.