Water strainers - graphical glitch or what?

[KittaDaDude]

Well, can you put water strainers on top of each other? Because every time I do the buttons do not turn green and I'm wondering if this is a graphical glitch or it just isn't working. Does there have to be a 1 block tall gap inbetween them?

[Catch22]

I'm not entirely sure of the bug you seem to be having but I will say stop using water stainers xD  They are decrept and should have been removed, geothermal generators and hydrodams work the same way just connect the pipe and they have no known bugs