[IslandReefer]

The $50 refractometer @ nano_reef.com looks just like the $100 Can one I have. This is the old style and I asssume thats why they are on sale. The new style has a different cal. screw set up, the old style cal. works great. As a Med. Lab tech I use refractmeters and have found them to be almost bullit proof; let the test water adjust to RT. (I leave it in the pipet for a couple mins, but doesn,t seem to matter if you don,t),put on 2drops and read...presto direct not inferred data....the best.
The test kits I use (as a lab tech ; I of course bought too many) are alk, hardness (dKH etc), nitrate, Ca and I use a pinpoint pH meter. A few more, like NH4 and nitrite I will usewhen I first cycle a new tank (ships today??). Also ,I find the Sallifert kits a bit mickey mouse..I have heard the Le Mott is better....but I don't know.
Hope this helps...One rookie to another
Good Luck