Ok I need to upgrade my system and add in some presurized CO2. The tanks that need CO2 would be 37, 50, 100, 125.

What size tank would work well for these aquariums?
Would it be possible to run enough CO2 from one tank to handle all or more than one?
What if I split them up per how they are in the room 50G, 100G together and 125G and 37G?

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Youd have to run them seperately I believe, your 125 will need more Co2 and your 37g alot less Co2 to get to the 20ppm range of saturation. I have not seen anyone run one tank on multiple tanks before. Not saying it cant be done with additional parts for each tank to control the amount going in.

What size CO2 tank though?

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

I use a 5# on my 210 about every 6-8 weeks. I think you might be better going with a 10# or two 5#' tanks.

I got mine brand new for $55 each. Im almost certain you are going to need 4x on equipment to deliver it at the right rates to the size of the tank.

I just found on Craigslist 2x20# 30 each one full one empty.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Two 10lb tanks may do for you, but the regulators will need to have dual manifolds on them. I just had greenleafaquariums make me one where I could run two diffusers in one of my 125s. Seems like you'd just be able to put in a y-connector and go, but air moves the path of least resistance and it won't work. Your 100g and 50g combo may take a 20lb...just to keep you from running out to get them filled so often. My new regulator has 2 ideal (the actual brand name) needle valves, 2 check valves, 2 bubble counters, and 2 outputs.

The person is in Baltimore, not trying to drive all the way there to get them.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

gotta be real careful with used tanks, the number two reason people sell em used it they are out of date, testing em costs a bit of money and most people wont go thru that instead will buy new ones every 5 years. Its a helluva price but can be a expensive deal as well.

Hydro testing is a PITA and only a few companies are federally liscensed to test the tanks.

If it were me, I'd get my tank already filled through aquariumplants.com. It will be a new tank and you'll have a little while before you have to look around for a place to fill it...which in of itself can be a PITA.

Im lucky for that, I got a filling station in the next town over, 15 bucks for 5# of Co2.

Ordering them full is EXPENSIVE if I recall correctly, I ordered my empty 5#'s from them.

Yes, the price difference is a good amount ($30-40). I only did it because it was easy and at the time didn't know of a place to have them filled.

You dont have a PRAXAIR by you?

Praxair welding supply? I dunno. See, at least that is a starting point. I didn't even have that, then.

look for a fire supply house Ben.

Beltway Fire Supply I think is what they are call or Service.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

You will need two CO2 bottles, probably 10 lbs each or higher, with dual gauge high-pressure regulators (the ones that screw onto the bottle), then two dual-output manifolds for each set of two tanks, then four needle valves, four check valves, CO2 tubing (NOT airline from your pet store - it will break down in short order), then some sort of diffuser or reactor to deliver the CO2 to your tanks. Rex Griggs has a great site to order all this stuff from, but be warned - he makes you jump through a few hoops to get your stuff and payment.

I agree that Praxair or AirGas are great to get bottles from. Also, if there are any home brewing stores around you they might do CO2 bottles as well (I go to The Beer Nut here in SLC, Utah). IMO, commercial-grade CO2 is better than industrial, though the cost is higher for marginally better CO2 (the only difference is commercial CO2 bottles are glass-lined, for (99.5% purity I think, while indurtial is 99.0%).

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Officially fishless until after the move....tune in later for details!

The question is .... are all four tanks near by? You can run a #20 with a 4way manifold.

As for refilling...I know some places won't refill but will do swap outs; much like the way they do propane tanks.

I would have to run some lines but 2 each are close enough to run off the same tank. I think I just need the dual regulators and #10 tank adjust each for the size of the tank and be all set.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Mike,

Here is where I got mine...you can pick any of their regulators and add on an additional manifold. The link just shows a regulator that mentions the extra manifold options Ultimate CO2 Regulator | Green Leaf Aquariums.

I bought the ideal CO2 regulator and added a manifold to have dual out. Getting ready to order another. Doing this could save you some money on tanks and regulators, although the price of the regulator is sort of high-end - for a single stage anyway, so the price could actually even out.

@James - you're right, I have a place here that will do that. It sucks if that is all you have around you and you bought a brand new tank.

PRO CO2 Regulator Solenoid(6 Outlets)+ 6 bubble counter | eBay


I've bought three of the single outlet regulators and have had no problems with them.

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