Sanitizing the tank

[AngelFishGirl]

How should go about doing this?
Angelfish Plague struck. Gotta completely start from scratch. Not a trace of water left.

Remaining fish are being temporarily rehomed. 10 gallon will hold one of my two filters with completely new filter media and I'm cycling the 10 gallon and then putting the filter media into the 55 gallon to cycle the 55 faster.

How should we go about getting the tank completely disease free? It's upstairs with no sink, and we can't empty and bring it downstairs to rinse :/

We were planning on chucking the water out the window.

How do I go about sanitizing the sand? The tank?
I understand using bleach will kill it off. So empty it(including sand), dry with towel, mix with bleach solution, fill partly with water, scrub, empty, refill, add dechlorinator? Is that the proper way to do it?

Thank you!

[Babakapusta]

Ooops, My bad. Retraction and apologies to you.