confused about dKH discrepency

[thisoldfish]

hey all,

I have a 65G mixed reef with 30G sump. SPS have been taking off and I recently started 2 part dosing w BRS pumps. Been watching my levels and pH seems to stay around 8.0, Ca 440 and alk around 8.5... or so I thought. I was using API kit for alk, and today decided to check w my salifert to make sure they match. Eh oh... the API today read around 9dKh while Salifert was 12dKh..

So, which one do I go with? Is there a control I can do? (Was thinking to test the water from my saltwater mixing bin? Should that be a standard dKH?)

For now I turned off my alk pump until I know where I'm at.

Any advice?

thanks

brad

 

[Justfebreezeit]

Id trust salifert between the two. Regardless if your corals are doing well id just keep it consistent.

 

[ihavecrabs]

I would definitely go with salifert as well.

 

[thisoldfish]

thanks- so dKh 11-12 is ok longterm? Everything has been doing well, and I think it's been a jump up recently because of the dosing- so I'm not sure if I should consider this "steady state" since it was recently bumped up.

Either way, as long as 12 isn't emergency level, I'll skip the next dose, drop each dose by a minute or so and keep checking with salifert and target 8-9. Just hope I'm choosing the right test kit (because otherwise if API is correct the dkh will go too low)

Wish these kits were more uniform/consistent! Seems like everything I have when compared to another brand is off

thanks

brad

 

[thisoldfish]

I'm an idiot-- I wrote Salifert but meant Red Sea for the alk test kit..

 

[acabgd]

I'd go with Salifert. That's what I'm using and also very recently confirmed by this evaluation: https://www.reef2reef.com/threads/lamotte-red-sea-salifert-alk-tests-evaluated.529932/

 

[David S]

hey all,

I have a 65G mixed reef with 30G sump. SPS have been taking off and I recently started 2 part dosing w BRS pumps. Been watching my levels and pH seems to stay around 8.0, Ca 440 and alk around 8.5... or so I thought. I was using API kit for alk, and today decided to check w my salifert to make sure they match. Eh oh... the API today read around 9dKh while Salifert was 12dKh..

So, which one do I go with? Is there a control I can do? (Was thinking to test the water from my saltwater mixing bin? Should that be a standard dKH?)

For now I turned off my alk pump until I know where I'm at.

Any advice?

thanks

brad

Unless it is a bad batch you want to go with the Salifert and this is against any test kit - let alone API.
You may be interested in my evaluation, in the following thread:
https://www.reef2reef.com/threads/lamotte-red-sea-salifert-alk-tests-evaluated.529932/

 

[nereefpat]

hey all,

I have a 65G mixed reef with 30G sump. SPS have been taking off and I recently started 2 part dosing w BRS pumps. Been watching my levels and pH seems to stay around 8.0, Ca 440 and alk around 8.5... or so I thought. I was using API kit for alk, and today decided to check w my salifert to make sure they match. Eh oh... the API today read around 9dKh while Salifert was 12dKh..

So, which one do I go with? Is there a control I can do? (Was thinking to test the water from my saltwater mixing bin? Should that be a standard dKH?)

For now I turned off my alk pump until I know where I'm at.

Any advice?

thanks

brad

What brand of salt do you use, and what does a freshly mixed batch test at with each kit? I'd be curious.

 

[thisoldfish]

Instant Ocean Reef Crystals..
I haven't checked fresh SW in a while but when I did I remember the API kit reading around 8.5

 

[David S]

I'd go with Salifert. That's what I'm using and also very recently confirmed by this evaluation: https://www.reef2reef.com/threads/lamotte-red-sea-salifert-alk-tests-evaluated.529932/

Didn't notice you had already posted.
Thanks

 

[nereefpat]

Freshly mixed reef crystals should be much higher than 8.5 dKH...assuming 35ppt salinity with a recently calibrated refractometer.

 

[iTread]

Hanna test kit...long run cheaper...just need to buy reagent

 

[mbmax]

Just to make sure re test both again and make sure you follow the instructions . API is not very accurate but the difference is too much.

 

[thisoldfish]

thanks folks

 

[ryeguyy84]

Hanna test kit...long run cheaper...just need to buy reagent

This^^^, love my Hanna. And reef crystals should definitely by higher than 8, maybe take it to the lfs for a second opinion