Root cellar design - one or two intakes?

We found a 8x4x3' pre-cast tank on our property and are using it to make a mini root cellar. Our understanding is that for small cellars, best practice is to have a low intake at one end and a high exhaust at the other - to pull the air/gasses through.

The tank has low holes on both sides, and therefore could potentially have two fresh air intakes - with a high centred exhaust.

In theory, two intakes would circulate more air, but might risk dropping the interior temperature too low - especially during cold snaps (we can get down to -25C). Looking to the permies community for any thoughts on which approach may be better! TIA!

No idea, but cool find! And hopefully someone else will have experience to help.

Great find and yes you would want to have air move through. floor to ceiling . Convection action. On saying this deflect or make indirect the air intake at the bottom . mix it up a bit.  if your in a really cold climate it would make a vary cold zone and could freeze.  have a door or valve to shut if its vary cold. Reason i say this is i worked in maintaining  large freezers and having cold air leaking into a medium temp zone could freeze product. Example delivery truck with zones for various foods cold leeks could bring temp down too low.  one thing is moisture level. not totally sure on how much humidity would be in it. often root cellers have dirt floors or vented wood for humidity  to be maintained. i would still give it a go.
cheers and good luck

A little more about what part of the world yo are in and what type of temps you get in the summer might be helpful.

good day i am in east coast of canada we range from 100 f summer to -15 f winter. summer average is well last summer was 75 to 80 hot summer this winter seams around 17 will be 32 next week . I plan to build a straw bail root cellar . i think 5 bx 5 entrance and a second door into a 8 x 12  7 ' tall storage area with a earth roof  gravel floor . I am on a slope west direction. hence the double door keep heat out . Oh and room for ice at the front need some for mint julips in the summer

your zone 8 i should have looked at your profile info. I am sitting in my log home at 55 f so thinking of cold was on my mind. what i am thinking of really dose not apply to you. you would have to deal with heat and humidity and insects more then me. still i would have a venting system to give you the option of humidity control . I would look at straw as well. i would sprinkle borax an DE through the bails during construction. Help denture bugs.