Is the 120 a new tank? Or a used tank?
Have you tried NOT running CO2 in the 120?
No. I set up the 120 to be basically the same as the 60 in order to have a successful transition for the livestock.
What bacteria starter did you use?
API, plus I moved a bag of biological media over from the 60
What are the ammonia, nitrites and nitrates of both tanks? And your tap water, too?
Will test again but this week the 120 had negligible ammonia and nitrites. Since the shrimp are fine in the 60 it seems likely that it and the tap will test OK.
I'm not personally familiar with EasyCarb but may try not dosing it at all?
It is gluteraldehyde, a source of carbon like Seachem Excel. I am not currently using Easy Carb in either tank. In the past I have used it in the 60P to help with some BBA.
Do you calibrate the TDS meter at all?[/quote]
It is an inexpensive one that does not have that ability.