I know your pain of moving house with fish tanks!
It IS stressful just thinking about it!
What I did was plan, plan and planned things in my head way in advance.
I had 4 tanks to move and the largest was just under 25 us gals / 110 litres so not a patch on your 500 litre tank.
What I did in the end was buy some cheap buckets from Wilkos, bought a bunch of fish bags of various sizesand some food crates.
Put all live plants in varying sized fish bags with a small amount of water. Put those in food crate with the tank decor / bogwood etc.
Pulled the external and HoB filters from tanks and into a bucket with some water, does not need to be a lot of water just as long as filter media is kept damp/wet.
Net all the fish and put separate specie groups in separate sized bags.
Netting fish is much easier without plants and decor in the tank, also draining about half the tank water gives the fish less space to escape to.
Then catching ALL those tiny cherry shrimps, was annoying tbh as there were many shrimplets that are so well disguised and hard to spot unless they move
Put the shrimps in fish bags with a little water and some java moss and IAL.
Put all the bags upright in the buckets, make it a nice snug fit so the bags don’t move around too much, cover with towels to make it dark for the livestock, less stressful for them.
And drain as much water from tank as possible, put some substrate into buckets with some water to keep moist and damp for the bb.
Once tank is pretty much empty as if you leave substrate in the tank there’s a risk of cracking the base glass so always play it safe.
Then move house.
And reverse everything in order, fill the tank with substrate and water first, use a dish or plate on top of substrate and put hose above that so the water flows straight to plate and this does not make a mess of substrate and cause messy water that takes ages to settle.
Add heater first to heat water and then filters etc.
Plants, don’t be too fussy, just add them into the substrate and you can sort this over the next few weeks after house move is completed.
Don’t forget to add tap safe / dechlorinator.
Add the fish straight into tank.
This will take at least 4 hours start to finish, well it did for me with 4 tanks!
Then have a cuppa tea and go phew am not doing that again!!
Edit - you only need about one third water to two thirds air in the fish bags with livestock, tie off by blowing air into bag (bit like a ballon)and double folding over end of bag and secure with elastic band tightly.
