Instant Ocean Reef Crystals dKH

[jbonez_]

So I just bought the Hanna Alkalinity tester and just finished testing it and it is showing a reading of 7.6dKH and my pH is about 8, from the research I've done, I read that Instant Ocean usually has a high dKH of 12.

My tank is relatively new but I want to start testing levels for corals as I plan to start putting some in within the next 3-4 months (give my tank some more time to mature), I plan to mainly stock softies with a few sps. Is there a reason why my dKH would be this low? Should I just continue to wait and see if it raises over time? I would like to see it around 9dKH.

 

[randomfishdude]

Check the solution to make shure its not expired or close to.
I had a simalar issue when I first got a tester.

 

[dwest]

So I just bought the Hanna Alkalinity tester and just finished testing it and it is showing a reading of 7.6dKH and my pH is about 8, from the research I've done, I read that Instant Ocean usually has a high dKH of 12.

My tank is relatively new but I want to start testing levels for corals as I plan to start putting some in within the next 3-4 months (give my tank some more time to mature), I plan to mainly stock softies with a few sps. Is there a reason why my dKH would be this low? Should I just continue to wait and see if it raises over time? I would like to see it around 9dKH.

So, you are testing the new seawater or your tank? If it’s the tank, normal alkalinity depletion (corals, coralline algae, etc.) might be the answer. Other possibilities are low salinity and issues surrounding alkalinity testing.

7.6 dKH is perfectly fine though. If it’s relatively stable, I’d be happy.

 

[Hugster78]

It’s a cheep salt. Inconsistency with that salt is common. Used it for years. Got tired of brown buckets and dkh swings. Did you make sure to stir the bucket before making a new batch?

 

[VintageReefer]

What salinity are you mixing to? IIRC I got dkh around 9 when I mixed to 1.026

 

[KrisReef]

So I just bought the Hanna Alkalinity tester and just finished testing it and it is showing a reading of 7.6dKH and my pH is about 8, from the research I've done, I read that Instant Ocean usually has a high dKH of 12.

My tank is relatively new but I want to start testing levels for corals as I plan to start putting some in within the next 3-4 months (give my tank some more time to mature), I plan to mainly stock softies with a few sps. Is there a reason why my dKH would be this low? Should I just continue to wait and see if it raises over time? I would like to see it around 9dKH.

Do a little water change and see if the dkh rises to evaluate the Hanna results. Old bottles of reagents have been found to produce lower than actual dkh results in the Hanna test.

Otherwise, as mentioned above the growth of coral and calcarous algae can quickly eat up alkalinity from a marine tank.

Figuring out how much is being consumed each day will help you determine how much alkalinity you need to supply each day to your system to keep the dkh stable. This stability is important for keeping coral long term.

Perhaps you can take a water sample to the lfs or have a reef buddy run a test to compare with the Hanna results. :smiling-face-with-sunglasses:

 

[jbonez_]

It’s a cheep salt. Inconsistency with that salt is common. Used it for years. Got tired of brown buckets and dkh swings. Did you make sure to stir the bucket before making a new batch?

Haven't stirred the bucket, I will do that before my next water change and see if that does anything.

 

[jbonez_]

What salinity are you mixing to? IIRC I got dkh around 9 when I mixed to 1.026

My refractormeter is reading 1.024 on the cusp of 1.025

 

[jbonez_]

Do a little water change and see if the dkh rises to evaluate the Hanna results. Old bottles of reagents have been found to produce lower than actual dkh results in the Hanna test.

Otherwise, as mentioned above the growth of coral and calcarous algae can quickly eat up alkalinity from a marine tank.

Figuring out how much is being consumed each day will help you determine how much alkalinity you need to supply each day to your system to keep the dkh stable. This stability is important for keeping coral long term.

Perhaps you can take a water sample to the lfs or have a reef buddy run a test to compare with the Hanna results. :smiling-face-with-sunglasses:

That's a good idea, I have to go there next week anyway so I'll take a sample there and see what they say, thanks!

 

[jbonez_]

So, you are testing the new seawater or your tank? If it’s the tank, normal alkalinity depletion (corals, coralline algae, etc.) might be the answer. Other possibilities are low salinity and issues surrounding alkalinity testing.

7.6 dKH is perfectly fine though. If it’s relatively stable, I’d be happy.

Testing my tank water. I'm completely new to Saltwater/Reefing, so you're saying corals, coralline algae, etc could possibly help raise the dKH?

 

[dwest]

Corals and coralline algae consume carbonates as they grow. So alkalinity will decrease as it is a measure of the amount of carbonates (and some other stuff) in the water.