There are no pH titration kits in this hobby; it is mostly a lab thing. In labs for seawater they use one indicator only for pH titration, Metacresol Purple. There are two companies in our hobby that sell a pH kit using MP; Instant Oceans, Aka, FasTest/SeaTest and Kordon's seawater kit. These are the best kits and most accurate there are, having the least "salt effect error" and the best color discrimination, where you can actually split the 8.2 -8.4 to get 8.3
Billy
RED
Yes, some kits use Phenol Red as an indicator which gives shades of Red
2thdeekay
Yes, testing pH isn't absolutely necessary if you're taking care of Alk
That is a common error
CO2 could care less what the Alk is. If CO2 enters or leaves the system it makes no difference what that Alk is the pH will either dorp or rise
Let's have a party at your house where the pH is 8.2 and the Alk 4 Meq / l and watch the pH drop like a rock into the mid 7's
Billy
RED
Yes, some kits use Phenol Red as an indicator which gives shades of Red
2thdeekay
Yes, testing pH isn't absolutely necessary if you're taking care of Alk
That is a common error
CO2 could care less what the Alk is. If CO2 enters or leaves the system it makes no difference what that Alk is the pH will either dorp or riseLet's have a party at your house where the pH is 8.2 and the Alk 4 Meq / l and watch the pH drop like a rock into the mid 7's
Last edited:
I swear the original post was asking about dosing, and getting it dialed in. 
