I'm afraid something is slowly leaching in your tank.
Your ICP test shows it in the metal part, even though the numbers are small but we all know how sensitive SPS can be.
You CAL is on the high side as well with over 500, of course that can be a one time event but not good for SPS.
CAL has been 500 for a long time and has remained with water changes. How can I decrease it? It reads 500 manually too
Would like to see what
@Randy Holmes-Farley has to say.
Advice is to use a detox (triton) for a few times and send in the ICP test again if no improvement something ain't right with maybe a magnet or just as simple a penny.
I completely emptied the sump 4 weeks ago, with no metals found. I cleaned all powerheads 2 weeks ago and did not find any rust or broken magnets, I keep my hammerhead glass cleaner in the tank, but checked it for any damage 2 weeks ago. Nothing is visibly rusty or broken. What else could introduce metals?
What size tank and how much flow?
The full system water volume is 400G, however the The 6ft x 36 x 24 deep tank has 2x Coralbox QP-16 ( Else mode, facing lengthwise on alternate corners, 2x MP40, 1x MP60 all on back wall, 100% ReefCrest,
Do you like flavored popcorn or used the regular?
Theres no popcorn in the house
What salt you using and how long after you mix it you do the change?
Using Aquaforest reef, mixed for 2 hours
Did you test your newly saltwater?
for Alk, CAL, MG, Salinity, yes
I would also hand test your ALK for a few day to see if big swings appear.
Have done, and still manually test every 4 days. It tests in-line with the KHG. My largest swing is 0.3DKH in a day
Don't think we dealing with a pest although vermite can't upset coral and cause poor PE but don't think it causes RTN/STN
For now stay away from SPS for a while like 3 months or so and try a small cheap frag on a rack at first in 2018.