Burr_nit buddy, don't sweat bro. They look great. Those little bitty humidifiers...Im not surprised, it's not helping so much in a big space. I'm sure you've seen me recommend the towel wick before...I bet it works better than those, combined.
20's surely aren't optimal but, once they get some heft to em, that's gonna go up...you know this.
Looking good bro!