Hold it .....
Leave the Kalk out of the equation while you're using 2-part - completely (I mentioned this once before)
Leave it in a cupboard in case you decide to stop using 2-part, but otherwise forget that you own it
Kalk will mess with your 2-part and confuse you
Having your pH drop overnight isn't an issue, and anything reading 8-8.3 during the day is all good
Don't fret over your pH, focus on your Big 3 and take it slow
You're trying to micromanage your tank and need to step back
Test your tank at the same time every day. I test mine about mid light cycle. You can do whatever you like, but test it away from dosing cycles
Just keep things between;
7-8dKh
410-420ish
1350
And don't panic if you're a bit off the #s
Start by testing daily with your dosers running and find a balance by adjusting your timers
Then switch to testing every few days or so once you see it's balanced
Then you can switch to weekly testing, or even go longer
Stop dosing Kalk
