what are the most importan levels to check for?

29gallon

i was just wondering what the most important levels to check for in a saltwater tank?

Pasfur

During the first few weeks of the aquariums life, obviously testing for ammonia and nitrite are critical. However, for long term success, I personally believe that testing for alkalinity, calcium, and nitrate are your biggest concerns.

Nitrate will hopefully remain at or near zero, especially in systems with a deep sand bed and adequate amounts of live rock to provide effective denitrification.

Alkalinity and calcium are the best indicators of the FUTURE stability of your tank. They are leading indicators, so to speak, that provide you with information about your tank BEFORE problems arise. Many hobbyists make the mistake of testing only for pH, which only gives you information after problems have already presented. Testing for alkalinity and calcium allows you to make adjustments on a routine basis, by simply adding a buffer and calcium supplement, or doing a water change when test results indicate the need.

I personally test alkalinity and calcium weekly in my 54 reef and 180 FOWLR. I aim to keep alkalinity at 8 - 12dkh, and calcium at 4000-460ppm.

29gallon

okay well i have had my tank set up for almost 2 years now and i dont test my water on any levels i do weekly water changes and clean everything monthly if not earlier and my tank is great...no hair algae nor randoms deaths..i have 40 pounds of liverock 2 my probably 25 to 26 gallons... should i even start with testing cuz i feel as if it is not needed..i know what all the levels mean but just dont feel like its needed

cerianthus

FO or FOWLR?

Once tank is well stocked with no intention of adding new fish and you have established the changes involved with tank water, I guess you can minimize the testing.
But would recomm testing from time to time since by the time fish show ill affect of deteriorating water condition, it may be too late.
If any testing show level where it should not be, just rectify so so slowly. I've read enough posts where people jump the gun causing more problem than is.