I use a Hanna alk checker, I really like it.
Testing and knowing your levels is a good idea, BUT "treat the tank, not the numbers". If everything looks good and is doing good, don't react just because you see some numbers on a piece of paper. Honestly, I haven't even looked at the ph reading on my ACjr in weeks. My tank looks great, everything is growing good, so there's no reason to fix something that isn't broke.
Support marine aquaculture, and share with your friends! Then you will find out who they really are.