DIY CO2 question

[phin]

on a DIY CO2 rig has anyone discovered a way to automatically shut of the CO2 flow into the tank durning non-photoperiods? Not manually removing it, but something automated every time the lights turn off and back on?

 

[aqua_chem]

The problem with this is that if you block the tubing in any way, you will create a back pressure that might rupture your reactor. Generally, DIY co2 is left on over night as most of the time the levels you create won't be high enough to cause problems, even at night. If it still worries you, or if you are running higher co2 levels, you can rig up an airstone on a time to only come on after your photoperiod.

 

[Cichlid Kid]

It's a shame there is no way to save and store all the co2 created by diy systems at night to then be used du
ring the photoperiod.
I agree with aquachem, it wouldn't take much pressure to rupture a 2L bottle or the airlines.

 

[phin]

The problem with this is that if you block the tubing in any way, you will create a back pressure that might rupture your reactor. Generally, DIY co2 is left on over night as most of the time the levels you create won't be high enough to cause problems, even at night. If it still worries you, or if you are running higher co2 levels, you can rig up an airstone on a time to only come on after your photoperiod.

The airstone is a good idea. Work to move the CO2 levels back to equilibrium levels at night. Thats good thinking. The KH of my planted tank is 2 dKH, the pH is stable at 6.6. I'm concerned with a pH drop at night with the added CO2.

On a different note, I switched from a Marineland C220 to a Fluval 206 two nights ago. I filled the top tray of the Fluval with peat instead of the carbon it came with. Since the trays are smaller in the 206 as compared tot eh C220, I have zero bypass of the peat. Since peat can be compressed very densly I've discovered that it makes a big difference in your results when you have zero bypass vs empty spaces/floss around the peat.

 

[Ilminded]

I was am having the same question, as I am about to set-up a CO2 reactor. So it's not a good idea to add a ball valve to control the flow of CO2 to the aquarium? I was planning on using a 2L bottle to a 500mL bottle with a little water in it as a bubble counter/gas chamber into a cut in half 500mL with a sponge in top half of the bottle where the line would go into the half cut mark and the CO2 would be force to go through the sponge where it would empty out the cap side into my filter to make sure I get max input. I was gonna put a ball valve on the cap of the 2L to control the flow as I have experiences doing that adding gases to chemical reactors and is what I am more comfortable with. I was planning to never close it completely as I have an air stone on overnight but would figure I could dial it back when lights go out. May I get some input?

 

[aqua_chem]

Using valves to control gas flow works with high pressure systems, but its not really effective at lower pressures like what we see in DIY co2 systems. If you reduce the area that the gas has to flow through, such as with a ball valve, the only result would be that the gas would pass through the smaller space faster, but at the same overall rate.