Carbon/thermometer

[Jason McK]

I don't use carbon that often but when I do I chuck it after I use it.

As for the thermometer I would place it away from your heater in a high flow area. Ocationally I will move mine around to ensure the low flow areas are not pockets of hot/cold water.
Currently my probe is in front of the baffle in the sump were the over flow water enters the sump and is slowed by the baffle.

J