I like Salifert mainly because I think they are easier to use. Not a lot of experience with other kits, I've used API (not bad, used the freshwater kit for my cichlid tank) and Instant Ocean (PITA really..hard to open the little packets, very messy)
Don't know how you would test the accuracy. I saw a thread on reef central where this guy was using a handheld
Phosphate probe to see how fast a phosban reactor was lowering his
PO4. It'd be interesting to test a kit vs. the probe.
Here's the link:
GFO (Phosban) Just how good is it??
