Yeah it make sense, when I was planning a high flow tank I used meters per second to work out how much flow I wanted.The circulation pump is rated 7500L/h
The canister is only rated 814L/h.
Taking away 15% for losses would put it at about 7100L/h or so.
That makes turnover roughly 25x.
This sounds like a lot but considering the flow of the water it is not much at all.
The water is moving but not as linearly as I expected. I may add another smaller circulation pump, maybe 3000~3500L/h and have that set on a timer with the lights. This would take the turnover to about 36x. But only while it is "day time" for the fish. Leaving night time to rest.
Again this is, in theory, and somewhat in practice, a 45cm x 45cm x 120cm column of water moving in a single direction so does not have the thrashing effect it would in a "square" tank. The column is 64gal of flowing water.
That is 1/4 of a cubic metre.
As the propellers are below the substrate, there is no jet effect that will hassle the fish leaving them a semi-homogeneous current column to play in. (If that makes sense)
Looks like you have a pretty good linear flow, looking forward to see how it all turns out.The double pump combo seems to be doing what I want it to.
Pic of both pumps. They are pointing up at the moment but will probably end up facing the bottom glass more to ensure nothing settles there.
View attachment 1339933
This is the clip of the water movement now. There seems to be less "backwashing" below the false bottom.
I will be emptying the tank tonight or tomorrow and siliconing the last few pieces of glass.
a. the plastic grating support for each side
b. The gravel border to hold back smaller pieces of gravel
Once that is done. The fun can finally start.