I apologize for the lack of info in my post, I was in a rush to get to work. I am going to confess that I am using DIY CO2 (1 2L bottle) on a 30 gallon tank so it is never turned off. It did not seem like it was building enough pressure to push back the water. I could always add a second bottle on a tee to increase the pressure though. There is a check valve on the line but I was wondering if it was normal to get backflow through the CO2 line. Would I have backflow pressure decrease if I connect the de-gasser/venturi outlet to the intake?

Edit: I made another reactor with a reducing tee at the bottom instead of a reducing bushing. The backflow was a bit less and my CO2 was able to overcome it.

Had a ton of problems with the top holes leaking when I tried this design. I used a 3/16" drill bit as specified. I also attempted to seal the rigid pieces in the top holes with aquarium silicone. After 3 tries and still leaks I gave up and built one of Rex's style reactors.

Sorry to hear of your troubles.

I've four of these reactor running and on each just used the same tubing as you did. Hole drilled same size as tubing and glued into place with PVC cement. Pre-fit the tubing into position, lift up about 3/16" apply PVC glue and push back down 3/16" with a slight twist. Locks up immediately and good to go. The tubing should fit snug while pre-fitting. If not the hole is too big and must start over or find bigger tubing. A word to the wise , If you build one of these reactors, build the top portion with the airline tubing before gluing to the 2" PVC (especially the clear PVC). That way if there is a problem with the air lines you don't waste the the 2" PVC.

Good ideas Mooner, if I ever get around to trying again I'll do it more carefully and in a more careful order of steps. I did hose my clear pvc too.

quick question, is the idea that the bubbles are trying to force their way to the top and the water is heading south so its mixing them really well?

You got it. The CO2 bubbles rise against the down-flowing current. The turbulence dissolves the CO2.

i built the reactor and it is amazing. Puts my tank to 30ppm in less then 30mins. Few questions though, i have it inline with my filter and dont have any adverse flow rates. If i rebuild it with bio balls will they 1)try and float to the top and also get tumbled around? 2) slow down the flow rate?

Also anyone have any extra clear tubing leftover they would like to sell? 12+ inches if possible?

I've got a closed loop 75 gallon tank with a iwaki pump (700+gph) and ocean clear filter. I also have a heater inline after the filter. Currently, I have my CO2 simply T'd into the line before the pump and it appears that all of the CO2 is dissolving. I'm pumping a lot (more than I can count) of bubbles and still the drop checker is not a nice green. If no CO2 is coming out my filter output then why am I not getting good CO2 levels? I can hear the CO2 get churned up in the iwaki pump so I know that my CO2 is not leaking out.

So...I am thinking about hooking in one of these reactors inline with this system. First, with my high flow, can I effectively use this reactor? I do not want to toggle down the flow to the tank. If it will work, how long should I design the reactor chamber t to be? Also, where would I link in the venturi line? My thoughts are that if I hook the venturi line in before the pump the bubbles will never make it into the tank anyway because they do not even make it into the tank now without any kind of reactor. Or should I just hook the venturi right back into the reactor? My thoughts are here that without any kind of pump to churn up the bubbles fine this will also not be very effective.

Here is a couple shots of my system before I setup the CO2



Here is how my CO2 system stands now...the CO2 line simply is T'd into the inlet before the pump


I'm sure another option is to put some Y's into my line and run another seperate pump dedicated to the CO2 reactor...this would require me buying another pump which I would rather not have to do unless completely necessary. With all the "stuff" I aleady have "inline" mabye this is not such a bad idea to prevent flow losses.

Also, is there another option for CO2 dissolution that I should look into? Keep in mind that I do not want to add any hoses or lines that go up and over the top of the tank. My tank is rimless for a reason - to keep all the equipment out of the tank

All opinions welcome!

Thanks for any help.
Matt

E6000


You do not use silicone on PVC. It's a poor sealer for pvc plastics.
Use E6000 or the blue PVC glue.
Then you will not have had the leak issues.
I've made 8 of them and not ever leaked.


Regards,
Tom Barr

See the part about PVC cement?

Always wise to use this, not silly cone when gluing PCV together for water tight seals.

As far as bioballs, you may add them, they should not decrease flow much.
Matt, I do not think the DIY reactor is going to do anything for you here vs a mazzei or adding the gas right before the pump intake.

It's should be ground to bits and you have pressure to burn with that pump also.
As far as the drop checker, please do not put too much faith in that device.
I've measure 4-6x differences in tanks' CO2 ppm's in real time.
Research suggest up to 7X differences in CO2 in and around plant beds.
I'm leary of drop checkers, you will not see them in my tanks, nor pH meters.

Regards,
Tom Barr