Ramirez said:
Do you recommend (or not) using a solenoid? From what I have gotten from other posts, using a solenoid may save some CO2, but causes bigger pH swings at night. I will be using it on a 55 gallon, if that makes a difference.
I have never, and I mean never, have seen any problems assocated with pH/CO2 and fish from turning off CO2 at night. Neither has Amano, it's taboo to add CO2 at night in Japan according to him.
So I'd have to say that is a simply a myth.
As stated, it will save you some CO2, if the lights are on for 10 hours, then you are saving 14 hours worth of gas. So generally more than 2x the gas.
I did not think they were worth it, but at 69$, it's hard to argue.
They use to be 40-60$ options, then they are not worth it.
You can stop gas from beinmg dissolved without a solenoid also(eg a reactor+ powerhead)
If you have many tanks running off a single system, placing the needle valves after the solenoid also prevents any small leaks that might be in the system while off, and allows some time to have the tank out gas at night so that there is not a high chronic level of CO2 in the tanks at night.
JBJ regulators are generally pretty reasonable as well, that would be the next choice. Bubble counters? Well, I do not use them, but some folks like them. I've never found a need for check valves.
Check around local fire Extingusher/Beverage places for cost of tanks, 10lb -20lbs are nice. 50$ for a 10-20lb tank locally here. 12$ to fill either. 18$ to hydro test the tanks after 5 years. One place was 8$ to fill. Cheap stuff once you have the tank. You can add more needel valves by adding a brass "T" and have two independently injected CO2 plant tanks for 12-35$.
Clippards are 11-12$ ea and the (old Nu Pro) Swaglock run about 35$. Both are good, the one that cost more is very nice and easier to adjust.
You can keep adding needle valves as your plant tank addiction continues.
Regards,
Tom Barr
