Help in choosing.
 

I am looking for a power head with the flow rate and price of the 6045. Is it controllable? When was the tenth anniversary? Is the blue 6045 controllable?

The 6045 has a mechanical flow adjustment, it is not electronically controllable, the 6040 or 6055 would be the equivalent that is electonically controllable and has a controller. The 6045 just has a mechanical flow regulation with 4 settings, roughly 400 gph, 600, 800, 1000. The 6045 came out in 2006, in 2016 they launched the anniversary model in Tunze Blue, they made them through 2020 but they have since been discontinued, a very limited number remain but likely within a few months they will be gone. The blue model has the same flow control.