55 gallon drum for mixing station?

[malawinovice]

Locals are selling 55 gallon drums, used.

Some are sealed with two bung holes, others with open top and sealed ring.

Which is better?

Some stored oil and others vinegar, some food in brine.

ideas?

 

[malawinovice]

I have historically used a brute 20 gallon for my water changes on 75 reef. With the use of a float switch 6 inches below the top rim and loss within the plumbing as I pump up stairs, I figure I was only changing out 15 gallons every two weeks.

 

[malawinovice]

I believe they are called tight head vs open head