Fts looks great! I found the easiest way to use limewater for me was a TLF kalk stirrer. I tried both the gravity drip and in ATO water also. With the stirrer i would first see how long it took to use up then set my phone calendar reminder when to change it. After realizing it took about as long as i did my wc and not wanting to both at once, i changed it in between wc.
I'm not positive but look into the Jebao dp-4 and see if that can be hooked up to the RA - i think it can. It can with Apex. You will get 4 dosers in 1. You can also add onto it with a 3 addon doser in the future. I will be dosing ALK, MG, CA, vodka and when I get the add on, K, Fe and I.