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1st attempt at Rex Griggs CO2 Reactor - Help please?

1967 Views 12 Replies 5 Participants Last post by  moke
Okay, so I decided to make a reactor given that the ones you buy are either cheaply made or made for higher flow than my canister. I know the normal design is with 2" pipe, but since my canister filter (Fluval 204) only puts out 150gph max, I thought it would be better to use narrower tubing. I used 1 1/4", since I already had that and thought it would work. I have it connected and to my surprise it doesn't the flow much at all. I used the biggest fittings that I could find that would work.

So here's my observation, and looking for advice on what size to use on my next attempt. Bubbles are coming out of my outlet and floating to the top immediately, so I did get rid of the "fizz" created by the diffuser, but at the expense of actually absorbing the CO2. It seems to actually be absorbing LESS than with the diffuser. I kept the bubble count the same and kept an eye on it.

So what should I try next, go with the standard 15" of 2" pipe like the design calls for? I was afraid of buildup at the top, given that my output is only 150gph, but it looks like the 1 1/4" has kept the flow too high. Another option would be to add a valve to increase the backpressure?

I should also note that my tank is 29 gallons, fairly heavily planted.
Fluid Electricity Electrical wiring Plastic bottle Circuit component

I could also try using this connector at the bottom to add backpressure to the reactor. See pics, much smaller opening.
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Fluid Liquid Font Ice cube Nail
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I don't think you have to remake this... I think you need to add a reactor bypass so you can reduce the flow through the reactor without limiting the water flow to the tank.

Here's what I would do: put tee barbs on the reactor in and out, then connect them with some tubing and a ball valve.

Like this:
Drinkware Liquid Fluid Art Cylinder

You can then use the ball valve to tune the flow through the reactor.
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