Low Alkalinity, need some advice

[eederise]

I'm a little concerned by the Alkalinity readings I've been getting. I've been testing somewhere around 2 - 2.25 mEq/L over the past few weeks. All other parameters seem to be OK and are as follows:

SG- 1.026 (refractometer)
Ammonia- 0
Trite- 0
Trate- <5 mg/L
PH- 8.2
Calcium- 450 mg/L
Phosphate- .2 mg/L

I just did a water change yesterday and the Alk has not budged.

I use Instant Ocean liquid tests.

I started using Kent two part calcium buffer about two weeks ago which brought my PH up by .2 and has stabalized my calcium level a little more, but the Alkalinity is being stubborn.

Any ideas as to what I could do to correct this? I will provide any info on my setup required to get to the bottom of this. Thanks!

[bertoni]

Most likely, the tank requires more frequent alkalinity supplementation. That's normal. Many tanks require daily dosing. I would raise the alkalinity to 3.5 meq/L or so, and start testing and dosing daily. You should get a clear trend line after 4-5 days.

This calculator should help with getting the right dose for raising the alkalinity:

http://home.comcast.net/~jdieck1/chem_calc3.html

Either the alkalinity part of your supplement or baking soda dissolved in RO-DI water should be fine. I'd use two doses to raise it.