Alkalinity...Why so high?

[xr4kw]

My Alk has been right around 14 for quite some time now. I have not added any kind of Alk buffer for more than 6 weeks.

Calcium = 410
Mag= 1280
Alk = 14

Any idea why? Can I lower it somehow? I've been doing 10 gallon water changes every week, the tank is a 72 gallon.

Thanks...

 

[bertoni]

What's the alkalinity of the water for changes? The test kit might be having problems.

 

[xr4kw]

I buy my water from my LFS so I never thought to test it. Will do and report back.

The test kit is Salifert but its time to buy a new one anyway. Should I try another brand?

Thanks...

 

[kgross]

Salifert are known as pretty good test kits, but you could pick up an inexpensive API test kit to compare it to.

I would suggest testing the water before you do a water change to see what the alk is of that water, and have the LFS test your water, so you will know if it is a true measurement or a testing error.

As for it dropping in your tank, what do you have for corals in your tank and how well are they growing?

Kim

 

[bgraves]

I have post some of the same probs before and still battling it now. My ro/di water for change outs has 14dkh with nothing and all other parameters in line. My dst has 18-22dkh when comparing a api and hagen test kit. Made a 10gal change this past weekend and gonna make a 10 gal this weekend to lower some.

 

[Icefire]

RODI have 0 dKH if it's at 0TDS aso I suggest a bad test kit. Salifert have some problem sometimes and give off higher than normal result.

Get an API to second guess

 

[bertoni]

Do you mean RO/DI with salt added? I agree that RO/DI should be at 0 dKH.

 

[bgraves]

Yes those reading are with salt added. I think I am dosing when I don't have anything useing up the alkalinity and calium the salt mix has and that could giving me a high reading possibly.

 

[bertoni]

I am surprised that freshly-mixed water is that high in alkalinity. I'd get a second opinion on that test kit.