Low alk on freshly mixed saltwater

philmck · 01/15/2006, 04:05 PM

Randy,
I mixed my first batch of Tropic Marin Pro this morning. Powerhead has been running in tub all day. Salt mixewd with RO/DI. Salinity measures at 1.026 with both refractometer and glass hydrometer. So I go test the alkalinity this afternoon: Three tests 5.7, 6.1 and 6.3 dkh with Salifert test kit.

The salt mix was prepared in the basement temp= 60ish degrees. Do you think that this is a CO2 saturation issue? Is the salifert titration temp dependant?

I don't usually test for alkalinity on fresh batches of salt mix, but with the switch to the new salt I though I would see if the extra money was worth it. Bad batch or wait a while?

thank you in advance,
Phil

Randy Holmes-Farley · 01/16/2006, 07:08 AM

CO2 has no impact on alkalinity. I don't know why this batch might read low, except the obvious of testing error or a "bad" batch. I'm not sure how high TM usually is, but that isn't all that low. Not much below NSW.
You can boost it with a little baking soda if you want:

Reef Chemicals Calculator
http://home.comcast.net/~jdieck1/chem_calc3.html

01/15/2006, 04:05 PM	#1
philmck Registered Member Join Date: Aug 2001 Location: Medina, OH Posts: 35	Low alk on freshly mixed saltwater Randy, I mixed my first batch of Tropic Marin Pro this morning. Powerhead has been running in tub all day. Salt mixewd with RO/DI. Salinity measures at 1.026 with both refractometer and glass hydrometer. So I go test the alkalinity this afternoon: Three tests 5.7, 6.1 and 6.3 dkh with Salifert test kit. The salt mix was prepared in the basement temp= 60ish degrees. Do you think that this is a CO2 saturation issue? Is the salifert titration temp dependant? I don't usually test for alkalinity on fresh batches of salt mix, but with the switch to the new salt I though I would see if the extra money was worth it. Bad batch or wait a while? thank you in advance, Phil __________________ Of all the things that I have lost... I miss my mind the most. Current Tank Info: 20 gallon reef

01/16/2006, 07:08 AM	#2
Randy Holmes-Farley Reef Chemist Join Date: Apr 2001 Location: Arlington, Massachusetts Posts: 86,233	CO2 has no impact on alkalinity. I don't know why this batch might read low, except the obvious of testing error or a "bad" batch. I'm not sure how high TM usually is, but that isn't all that low. Not much below NSW. You can boost it with a little baking soda if you want: Reef Chemicals Calculator http://home.comcast.net/~jdieck1/chem_calc3.html __________________ Randy Holmes-Farley Current Tank Info: 120 mixed reef