alk test question

[reefkeeper78]

I have a question about my test kit. Is KH (says on the bottle KH carbonate hardness) and a DKH test kit the same thing. The lfs said it was the same thing but I'm starting to question that due to my ph readings and alk readings. ph reads 8.03 and KH (alk) is 11.5 but I can't get the ph to raise by aerating the test sample.

[bertoni]

How long are you aerating the sample, and how?

[reefkeeper78]

well I figred for a small sample, drinking cup size, about an hour though I jumped the gun because I figured I would see some sort of change in a few minutes. After 10 I hadn't seen it move at all. I came back an hour later and it had increased to 8.16.

So if my fresh saltwater is rich in co2 then adding a pump and or air stones will help blow it off. Once the ph rises will it stay that way or will it naturally fall again?

And are dkh and kh the same thing?

[bertoni]

dKH and KH are used interchangeably in the hobby. There are lots of units used in reef-keeping:

http://reefkeeping.com/issues/2005-08/rhf/index.php

You could try aerating a cup of water inside next to the tank for a few hours. If it rises, then more aeration of the tank should help the pH. Otherwise, the room needs more fresh air. A limewater drip sometimes helps, as does a carbon dioxide scrubber for the skimmer input, but 8.0 is fine for pH, IMO.