Re: [APD] Re: CO2 Questions

[Bill Wichers <billw at waveform_net>]

> What if you want 30 not 8? Can I use an ABS plenum, pressurize it to, say,
> 3-4PSI
> then just bleed straight off that into tha tanks? (Like I do with air pumps)

Yes, you can do that. Remember that you're probably not going to have the 
same volume of gas going through your CO2 manifold as you have going 
through your air manifold, so you can get away with smaller tubing and not 
loose much performance. Personally, I would use copper refrigeration tubing 
and fittings (it's like copper water pipe for dollhouses -- all the same 
fittings and valves, but in sizes like 1/4" and 3/8"). The copper tubing is 
a *lot* more work to use, but it gives a very nice permanent installation, 
does not degrade over time, and looses no CO2 from diffusion (which is of 
minimal concern due to CO2's low cost, but some people worry about it). I 
have also used 1/4" LDPE tubing for long runs with good results, and that 
tubing is cheap and easy to work with. 500' was about $15-20 or so.

You'll probably want separate needle valves for each tank so that you have 
some independent flow control for each tank. I suppose you could use one 
valve at the beginning, but you'd then have the same kinds of balance 
problems multi-tank air systems have, but in this case the imbalance 
between tanks would result in water chemistry problems.

It would be worth pointing out that if you use a common filtration system, 
the multi-tank CO2 distribution problem is moot -- one injection point 
would feed the whole system.

     -Bill


*****************************
Waveform Technology
UNIX Systems Administrator

_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo/aquatic-plants