Kalk addition

[allof fish]

If running Kalk in the ATO make sure the container is fairly sealed up, Especially if you plan to have it cover 7 days. When exposed to air it is supposed to loose the PH effect. When saturated and stored it will make a film across the surface blocking the air.

Our tanks sounds like they will be very similar in stocking.

I can't help with the ATO with Apex. I run old school JBJ ATO units.

Yes I have it plastic wrapped shut as I don’t have a lid for the tank but it’s as airtight as I can make it. Going to just run this kalk for a week and test each night and fine tune my 2 part to my liking. Wa just worried about it getting to high without any way of knowing starting off

 

[allof fish]

Right — I’ve always struggled with the last part “if the dose is appropriate” ;)

So I would just pick one method as primary and supplement as “appropriate”. What I did on my other tank: switched to kalk exclusively and used 2-part for fine-grained control. That’s what I’ll recommend for the OP - switch this around.

I agree

 

[backbayreef]

Speaking of ato with kalk, kinda off topic but does anyone know why I can’t put my ato on auto in my apex. I thought it used to be like that but want to put it on auto incase my ph gets too high. Currently just set on

Apex processes top to bottom. In this case, why don't you just make it simple like so? By default, turn it ON, otherwise, OFF.

Fallback OFF
Set ON
If Swx1_1 CLOSED Then OFF
If pH > 8.4 Then OFF
If Output return = OFF Then OFF

Note: looks like your syntax is incorrect hence it's not executing.