What Size C02 Tank Should I Get?

[msebar]

Trying to find out how long a 20lb tank would last on a 180 gallon tank and at what rate? 

 

[techen]

A 9KG tank of CO2 on a 180 gallon, Depending on how much light is being pushed into the tank, I'd at least say 4 months.

 

[KirkyArcher]

Most people get a gas bottle that would fit in their tank cabinets or stand them by the side as discreetly as possible, how long will it last will depend on how much light you have, how many and type of plants and your water hardness, and diffusion methods. My 3kg extinguisher bottle at 2 BPS lasts about 6-7 months of eight hour daily run time, so based on that your 20lb tank should last a good 6 months to a year.

 

[msebar]

I am looking to plant moderate to heavy with about 75 3 watt leds. I am looking into a 20lb tank which is about 9kg. If I get 4 to 5 months I would be happy.
 
What would you say the BPS should be?

 

[techen]

The BPS depends on your drop checker, Whenever it turns green is your BSP on that set up.

 

[msebar]

can someone recommend a good solenoid for a 20 pound tank.