Need advice on testing

[EatFood]

Is it normal for calcium and magnesium consumption to be 0? tested with salifert and I tested alk with hanna checker.

Tested yesterday and today at the same hour the parameter where Calcium 415, Magnesium 1260, Alk went from 8.5 to 8.4 and I have like 20ish sps frags from 2-3 inches.

 

[Saltyreef]

Test over 5x days and then average out the data to get your average daily consumption rate.

Also, run the test 3x to be sure its reading correctly.

You wont see mag drop too fast either.
About 1/6th slower than the alk and cal.

Hobby grade test kits you have to do some trial and error.

 

[PatW]

SPS frags only consume alk and Ca when they are growing. Frags often just sit and after some time decide to grow. Also frags are small and even when growing will not consume much. So your experience is not out of norm. An SPS dominant tank with big growing colonies can easily consume over a DKH per gay requiring automatic dosing.

 

[mdb_talon]

Very normal if dkh dropped .1

Testing variance alone may mean alk dropped 0, but in any case you will see alk drop much faster than calcium (and MG even slower).