55 gallon blue barrels buckle
They seem to be an inexpensive way to build a system, however, they have challenges. The buckling means you need to build a good structure to hold them.
55 gallon blue barrels are round
I know, duh! We went in knowing they were round but not realizing how difficult building siphons would be with a round bottom. We've made it work but they are a bit more fussy than systems with flat bottoms.
Aquaponics is truly an ecosystem