Maintaining Alk w/ PO4 Reactor

[brians_224]

Hi Randy, et al -

I've been running a po4 reactor with Pura PhosLock media for 2 weeks. I started the reactor with one teaspoon of media and have slowly been increased to a total of 3 teaspoons over 7 days. My total volume is 65 gallons. Very lightly stocked. I've been testing my alk and calc almost nightly. My alk seems to hang around 7.5 despite my addition of 1.5 - 2 teaspoons of baking powder nightly. My calc is stable at 425. Previosly I kept my alk around 10. I top with kalkwasser - although my top off volume has decreased since the nightly drip of baking soda. I use a salifert alk test kit.

Am i doing anything wrong in my method? Whats the maximum amount of baking soda you would add during an overnight drip? Should I switch to washing soda instead and decrease the amount used?

As always - thanks for your help!

 

[Randy Holmes-Farley]

While I don't prefer reactors that stir the media, any drops in alkalinity that you see can be offset by adequate baking soda (and perhaps calcium, as in a two part). I'd just add more daily and see what happens.

Washing soda would not be any better. If you want to raise pH too, I'd just bake the baking soda before using it.

 

[brians_224]

Thanks for your quick reply...

I'd just add more daily and see what happens.

Meaning increase the amount of baking soda added daily? If so, is there a risk of over dosing?

 

[Randy Holmes-Farley]

If the alkalinity is low, and calcium is adequate, there is no risk of overdosing baking soda (except when alkalinity gets too high).