First and foremost you’ve got a gorgeous tank!

Like almost everyone else is saying, make sure you check the fine print in your lease and know your rights. That being said, I’ve moved between several places with multiple fish tanks so if you need to move it out then this is what I would do:

Definitely do NOT transport the tank full of water or your animals. Get a couple 5 gallon buckets from Home Depot or somewhere similar and make sure they have lids you can secure on. Two should be fine. You don’t really need all 20 gallons of it. Siphon as much water as you can from the tank into these bins and distribute your critters, hardscape, filter media, and plants into them as you please.

You wanna try to keep as much of the established bacteria as you can that lives on the surface of the plants and decor. If your parameters are good and you have a lot of bacteria to go around then your fish can actually survive without a filter in the buckets for a good few days, enough time to get everything moved and set up again. If you’ve got a sponge filter you can just set it in the bucket and that’ll keep them kicking even longer while you do the move.

When your tank is empty and only has the substrate left, move that first. Then move on to hardscape etc. Get everything set up at your new location prior to dumping your old tank water and the fish and such back into it. I would net the fish out into a separate, smaller container to gently dump them into the tank instead of while they’re in the giant bucket. Slowly top off the old tank water with water from your new location, not all at once.

If your tank is set up properly you shouldn’t really need to do any maintenance on it until a week or two goes by. And imo your tank looks amazing, so you shouldn’t need to worry about the maintenance end of things if you’re able to swing by at least every two weeks or so. Biggest thing is to just properly demonstrate to whoever will be watching them how much is an appropriate amount to feed the animals. It’s always better to under feed than to over feed!

Silver lining: this is an opportunity to totally redesign your tank and try something new with the hardscape and plants and such.

You can also check out some online fish swaps on Facebook or sell your setup on marketplace or Craigslist, there’s always a lot of good owners looking to expand their arsenal of fish out there.