April 19 2007
Got my aluminum 10# CO2 cylinder today. Still have to wait for my regulator though which I'll hopefully get next week from Rex.
One of the main flaws in my setup is that for filtration, I am using a wet/dry. I've researched the wet/dry in a planted tank and the general consensus seems to be that it'll outgas the CO2 too much, requiring the CO2 input to be pumped up. During the course of my researching, I came across some information from Tom Barr who stated that the actual trickle area in the wet/dry is not the main source of CO2 outgassing, but rather the overflow. Decreasing the fall of water from the overflow will substantially decrease CO2 outgassing. And as for the trickle section, sealing the top area off (w/ tape, etc.) would create a large reactor where CO2 would degas, then be reabsorbed.
Sealing the trickle section would be easy, but I place a sponge filter inside and removing/reapplying the tape would become a hassle. So I've come up with a simple (and hopefully effective) design for the overflow which would decrease the distance of water falling and which would incorporate a sponge filter to trap larger debris.
Here is how the original overflow on my tank looks :
And here is the design I've come up with :
It might be a bit difficult to see the concept since I'm horrible at making graphics. I will be sticking a long piece of PVC pipe into the outlet of the overflow tank which will block off any water going directly into the wet/dry. This will cause the water to rise up until it reaches holes in the PVC which I will be drilling. This will significantly minimize the distance which the water overflows.
So what's with the cylindrical cap (which by the way won't be red)? Well, after thinking about it, I figure that some of the CO2 outgas from the trickle section may find it's way up to the PVC and out into the atmosphere. Thus, the cylindrical cap. This will be siliconed to the top of the PVC pipe and will extend down below the water line. This way, any CO2 which may reach this point will have nowhere to go, trapped inside the cylinder by the waterline. At this point, I can easily add a sponge filter at the top for quick filtering of any large debris.
Sure I could go out and purchase a canister but I'm broke now after buying my CO2 setup and I still have to purchase a diffuser and more plants. DIY is fun anyways
If you see any flaws or have any advice/suggestions/comments, let me know. Thanks.