Thanks. The third line with the elbow is the ATO line. The doser is a Jebao DP2. They're ok but not super accurate and probably won't last that long the way I'm using it but it fit my cabinet. I also hooked up a DP-3 slave to it on the other side.
I'm going to try the Aquaforest 1+2+3+ balling method for dosing. I've read good things about it and it seems pretty easy, dial in your alk and dose all 3 parts the same and everything else should balance out. Seems idiot proof which is right up my alley

.
I did have an issue with my fuge. The light was too strong and melted my chaeto and grew a ton of GHA. I had to dial back the photo period and block some of the leds (see pic). A couple of Trochus and Margarita snails went thru the GHA had it looking like new in a few days tho!!
A good sign... pods all over the place!