I currently use nothing but Salifert, and I think they're the best for the money. I have a LaMotte test kit for Nitrate and it's pretty nice, but I don't think worth the $.
I usually test for Alk and Calcium daily, but only because I recently switched from a 2 part additive to Limewater with a top off--I test daily to establish a pattern for Calcium and Alkalinity consumption and dosages.
I do agree that testing for salinity is an essential daily practice, and a refractometer is such an excellent and convenient way of checking it--I replaced a hydrometer 6 months into the hobby w/ a refractometer, and found out just how inaccurate they usually are--what I thought was a 1.025 salinity was actually 1.031!!
Cycling test kits (ammonia, nitrite, nitrate) are nice to have in the beginning, or for emergencies, or for measuring shipment water your livestock comes to you in. (I just like checking how much toxins are building up in the bag over a 24 hr. period.)
A good ph kit (I recommend Salifert) is a necessity also. I usually check mine every other day or so.
Nate
