I think the biggest problem you're going to have in a 5g bucket would be ammo and water changes (still the 3 fish in your profile?). Maybe a 30g garbage can would do better for you. If you had one of those around for mixing SW
in that would be great. Then a couple of pieces of live rock, a power head and a heater and you're all set.
Keep the bio wheels in motion in some water (with an ammo load preferably (shrimp? food?)). If you're going to replace the sand that you had then you'll probably see a cycle as you may be tossing out some of your load bearing. Did you save a cup to seed the new sand? If so all the better.
Keep the live rock heated as well (again a powerhead would be good here).
Good luck and be sure to update us on your progress!
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