I have two of the bristlenose plecos in my 150. They have just about put my nerites and pond snails out of business.
I am curious about what you said about shutting off your CO2 at night. If you have your controller set to turn off CO2 at 6.2 while not just let that take care of things? That is what I was planning to let my Aquacontroller do. What am I missing?
Basically I am shutting the co2 off at night because it doesn't do any good to pump in co2 when the lights are off and plants aren't photosynthesizing. Then my co2 tank lasts longer. Also when I was researching using a ph controller to completely control Co2, I found that your kh can change for various reasons like when you do a water change or possibly with fertilizers. It affects your ph and then by default your Co2 levels. This way the co2 level stays more constant and the fish are safegaurded from a major malfunction or ph drop.
I'll have to seriously look into one of those bristlenoses.