Re: CO2 reactor placement, post or pre?

[Thomas Barr <tcbiii at earthlink_net>]

CO2 reactor placement, post or pre?

The post filter side has to deal with the vertical head pressure in the
line. Does the prefilter line also have head pressure to deal with?

Why is there a limit of the height a canister filter will be able to pump
water to (w/o reactor added)? Is this merely from the frictional losses of
the water/sides of the hose?

But you can place a larger input diameter in the suction side, generally
3/4" in, and the output side will be 1/2" out.  Many/most pumps/canisters
work best with a larger suction side and small output for good head pressure
lifting with minimal flow rate losses as the head increases. Many filters
are also set up this way(Via Aqua that I have etc). As the head pressure
increases, pump designs go to different smaller sized outputs to make up for
for this.   

This results in better flow with this placement rather than post filter.

The barbs added to your DIY CO2 reactor can be varied to accomodate the
larger inlet hose diameter.

Less flow restriction/friction = less work= more flow. Less head pressure=
less work= more flow.

The other thing is simpler vertical placement. With post filter placement,
you would need a loop going in the top and exiting the bottom since the CO2
reactor requires vertical placement to prevent bubbles from escaping out the
bottom. This results in longer hose return lines/total length. Longer pipe
length= more friction = more work= less flow.

It's easier to put it at the pre filter side as far as installation goes and
the potential for leaking is less on this side as well.

Regards, 
Tom Barr