What electrical circuit does a home bitcoin heater need?

Short answer

A 240V circuit. The Aqueon plugs into a NEMA L6-30 receptacle on a 30A circuit, often the one an electric water heater already uses. HashTub home heating needs a dedicated 30A, 240V hardwired circuit, and a complete Snorkel HashTub uses one 60A GFCI spa circuit.

SetupCircuitNotes
Aqueon Hydro240V, 30A, NEMA L6-30Rated 5 kW; verify the circuit handles 5,500 W at 240V. Hardwire where code requires.
HashTub, home heatingDedicated 30A, 240V, hardwiredPump and miner breakers come pre-wired inside the enclosure.
HashTub retrofit kit25A, 240V on the tub's heater circuitPowered only when the tub's control board calls for heat.
Complete Snorkel HashTubDedicated 60A, 240V GFCI spa circuitRuns the whole tub, per NEC Article 680.

Supply wiring should follow local code. Use a licensed electrician if you're not sure.