It depends on what parameters you are trying to measure and maintain.
Generally speaking, ammonia, nitrite, and nitrate tend to keep themselves in check so long as you have adequate biological filtration. It’s good to keep an eye on them as they can warn of an impending disaster, but I never test them myself.
Phosphates might be helpful to monitor, but I’ve found that a healthy algal refugium often keeps those in check in a mature system. Again, I never test phosphate unless I’m having some sort of issue. Generally speaking, you have too much phosphate, you’re going to see a nice algae bloom.
The other three commonly tested parameters are calcium, alkalinity, and magnesium. Those three are directly related to coral growth. Testing and maintaining them is a topic that could be covered in multiple threads. Very quickly, this can be done as easily as testing just calcium and dosing a one-part calcium additive like Tropic Marin biocalcium or as complex as owning an automatic tester that tests all three of those parameters automatically which then doses either a two part or three part additive solution automatically. The first option will probably cost $50-$75 to get setup while the last would require well over $1,000 in equipment to get going.
My parameters we're up and down got it under control now..
Salinity - 1.029 Temp- 78.9 CA- 440 ALK 8.5 MG 1600 PH trying to raise can get 7.8 it's at 7.6 but I think die to it being new tank. PO4 - 0.02 Nitrate 5 PPM.
I was looking at the Reefboot what are your thoughts on that. It pricey. I think it those way more than the trident? Not then again don't have an apex yet still saving it's expensive plus what going on right now have to think 10 time as I have 3 little ones