2 filters 1 line.

[40GallonsOfDoom]

Well after doing some reading on the subject, I've found some more information backing my design. Thanks for the tip on fluid dynamics in a closed system @sir_keith. As I found before the hoses and Y connectors pose little to no effect on the flow through the system as their size is substantially larger than what either or both filters/impellers can produce, the way they are designed the filter media itself is really the only impedance in the system. So the additional filter on the system will only add pressure to the output, which again, due to the size of piping etc will not be a problem. End result, more flow, more circulation, better filtration. Will update when new filter arrives and construction is completed.

 

[DMD123]

Kind of just a thought here, but you are assuming both filters are running exactly the same gph and they will fill up with waste and perform identically... If for some reason one gets clogged faster or is not identical in output wouldn't that put some additional backpressure on the one already having to work harder?

 

[40GallonsOfDoom]

Kind of just a thought here, but you are assuming both filters are running exactly the same gph and they will fill up with waste and perform identically... If for some reason one gets clogged faster or is not identical in output wouldn't that put some additional backpressure on the one already having to work harder?

Well I've decided for ease of design to just stick with another eheim like what's on it.
As far as the back pressure, no it won't cause back pressure. The pumps work off of gravity(siphoning). The reason the pump is after the media is because it's design is to put just enough pressure to push the water over the top of the tank and out. The inlet is actually pulling water in at the rate it is due to the siphoning action created by the pressure the pump is applying to the water going out. The slowing of one impeller won't change the amount of siphoning of the other impeller. Also you can look at dual sump pumps in basements. Many of those are also on y connectors. As long as the output is large enough to handle the volume of water, they don't interfere with each other. The system will only pull as much as it handle.

 

[DMD123]

I do seem to remember the Eheim using a metric sized tubing and it was a challenge to hook something up to it when I had a Eheim canister, likely an inline heater or UV. I ended up having to dip the end of the Eheim tubing in boiling water to be able to get it soft enough to fit where I needed it to. Take some pics when you get it set up and show us how you did it.