Are Salifert test kits just expensive junk? Ive been using the calcium one and according to the kit Ive been maintaining my calcium at around 450. But corals and coraline have been bleaching. So I test the reference sample from my old seachem kit which is 425. The salifert kit gives me over 500 and the seachem kit gives me 420. So then I test my water with the seachem kit and get 350. Thats 100 units off! I'll only buy seachem kits for now on just for the reference sample