AndrewH, i really like your design, could you give me any feedback as to how it performs? also, have you filled the reactor with any media to help dissolve the co2?
I did build the reactors and I have all of the CO2 equipment (15# bottle, M3 2 gauge regulator, solenoid, needle valve, bubble counter, tubing), but I get such great growth with just lighting and refilling the evap water (no water changes) that I don't need to hook up the CO2.
One of my bulbs burned out on my 2 lamp T5HO fixture and for 2 months I left it with 1 bulb to see what would happen. Before with both bulbs I was trimming the tank twice a month (every other week). My tank was almost bare after the last pruning before the bulb bared out. I replaced the bulb 2 months later and there wasn't any change in the plants lengths or color within that time period, but as soon as I put in a new bulb the plants are now taking over the tank again - 7 days later
. I didn't photo document the dramatic change when it happened, but plan to recreate the situation so I can document it. Should be pretty interesting. And if I'm getting this type of growth with just lighting (no ferts, no chemicals of any kind - no dechlor, but doubled filtered tap water), I don't think I want to increase that by adding CO2... I couldn't keep up.
But to specifically answer your questions: I did not fill the reactor with media material (like bio-balls or pillow stuffing) because I completely sealed mine. It being below the tank I didn't want to run the risk of a threaded joint not getting tight enough (as in cross threading it by accident) and it leaking all of my tank water onto the floor. Also, I feel the length of the reactor will allow the CO2 to be completely dissolved. It's sealed, so where else is it going to go besides into the tank? But the reactors I actually built (and in the pictures) are ~24" long. There's plenty of length to cut off the end and put in a female adapter, reducer bushing, and a hose barb so you could get into the reactor to clean the media.
A friend of mine built some reactors that look kinna like my design (minus the heater part) and is reporting great success and lots of dissolved CO2. He's on these boards as "rolloffhill" (I'll send him a PM to see if he'll comment on his reactors and how he likes them).
Originally Posted by eyebeatbadgers
I've been using an almost identical setup for about a year now, and it works perfectly. I used it to dissolve my CO2 for a while, and it did not need any media inside it to break up and dissolve the CO2 for my filter. If you are running a very powerful filter, you may need to increase the length of the PVC. The only thing that I would like to point out is that you may have to calibrate your heater once it's installed in the unit, as the way it is set up caused mine to overheat the tank by about five degrees. Once I recal'd the heater, it's held a steady 78* ever since.
From what I calculated (mostly just guessing) a normal hang-in-tank heater will be much more efficient in this configuration. It's meant to sit in stagnate/slow moving water and keep the temp at say 75*, but if you put relatively fast flowing water over its surface in a confined space it should only take the same temp equivalent as say 70*. What used to take 75* is now taking 70* and probably not running as much/coming on as often since there aren't as many cold spots (I guess that really comes down to how well you're circulating the water throughout the tank = how often the heater as to come on).
Lowes and Hometheftpot carry these fittings too. Although not all of them do. Mouser is a good bet.
I found that the Home Depot and Lowes in my area didn't have the same stuff. In fact the HD had tons more options than Lowes (I was disappointed because the Lowes is close and the HD is a few miles away).