Test kits and frequency of tests that should be run?

[Myka]

I don't have a calcium reactor, I dose instead. If I do regular waterchanges then I don't usually have to dose as long as the levels of the waterchange water are good.

I notice you are dosing strontium, but you are not testing for it. Personally, I would never, ever dose anything I can't test for. For having just set up your tank, I think you are wasting your money testing for a lot of the stuff that you are, and you shouldn't bother dosing with anything until your cycle is over.

As far as testing during the cycle, take a peek at this Guide I wrote about cycling tanks: http://www.canreef.com/vbulletin/showthread.php?t=44859

After the cycle I would check calcium, alkalinity, and magnesium and get those correct before adding corals. I would check those levels once a week until your tank matures a bit, and you are getting steady readings week after week, at which point I would then only test every couple weeks, monthly, or after each waterchange. Magnesium isn't used up very quickly, so I only test for it every month or so, or after a waterchange.

Strontium and Potassium are kind of "bonus" tests, and I would treat those like Magnesium as they don't get used up quickly, and therefore don't change quickly, so i would only test monthly after the readings stabilized.

I tend to do most of my testing the day after i do a waterchange just to check that everything is in order. I do monthly 30% waterchanges, but often my tank goes for 2-3 months bewteen waterchanges, at which point I will test for calcium and alkalinity, and dose those accordingly. I can get away with so few waterchanges because my tank is over 2 years old now, and all the corals are well established. Plus, my corals are all LPS, not SPS. I'm not sure SPS would take so kindly to being ignored for so long.

I noticed you didn't list an alkalinity test kit, and that is very important, so you will want to pick one up.

Also, I see that your specific gravity is 1.020?? That is far too low. That level of salinity is considered "hyposalinity", and is only used temporarily as a treatment in place of medication for certain diseases, and issues. Your sg should be 1.025-1.026. When you raise your salinity you will raise your levels of calcium, alkalinity, magnesium, potassium, and strontium. You may need to do a couple waterchanges to get the levels back down.

I don't know if you're interested or not, but the levels I like to keep are:

Ammonia 0 (not accaptable to be anything other than 0)
Nitrite 0 (same as above)
Nitrate 0 (5 ppm at the most, but mine never goes above 0.1 ppm)
Calcium 415-425 ppm
Alkalinity 9-9.5 dKH
Magnesium 1340-1360 ppm

Personally, I think your calcium level of 500 ppm is way overkill, and really just a waste of money. Also, calcium and magnesium need to be in proportion to one another for maximum adsorbtion by corals. Balanced calcium and alkalinity levels:

1.4 dKH to 350 ppm
2.1 dKH to 375 ppm
5.6 dKH to 400 ppm
9.1 dKH to 425 ppm
12.6 dKH to 450 ppm
16.1 dKH to 475 ppm

So by having 500 ppm calcium you would need your alkalinity to be somewhere around 20 dKH to be balanced, and that's just silly. By having your magnesium on the low side, and your calcium definately on the high side you risk the calcium precipitating out. The higher the magnesium the higher you can keep your calcium (and thus alkalinity) without so much risk of precipitation.