Hi JH!
I have moved MANY MANY times with my tanks... here's what I did.
First off, I moved my tanks last. I made sure all my furniture was in the new place, and then I made arrangements to move my tanks. This isn't always possible, but if you can, it will make things easier.
I picked up some styrofoam fish-boxes from the local outdoor store, and using my python/gravel cleaner, I filled them all up with water from the tank. The amount/size of fishboxes really depends on how many fish you have, and how big they are. It is very important not to overstock these, as the ammonia will build up quickly. Also, don't go too big, don't be buying one of those 3 foot long styro cooler's because you'll snap it in half once you try to move it with water in it. Once the fish-boxes were full of water, I divided all my fish into them, trying to keep schools together. The next step in taking down my tank was going to take some time, so to keep my fish as less-stressed as possible, I placed heaters in the styro fish-boxes, as well as air stones hooked up to air pumps. Then I put the lids on as much as possible to avoid any "jumpers". I moved these out of the way so I could get on with the rest of the tank.
I had an extra styro fish-box that was for my plants, my substrate and my filter media. I filled this box with water from the tank, then added those things to keep them all wet (bacteria... aka bioload).
Then using camping jugs that I had around and garbage cans and buckets, I salvaged as much water as I could move. If it's a short trip, make a couple of trips if you can. Just don't move any water in the tanks, as it could cause stress fractures. If you really aren't able to move most of the water or as much as possible, for whatever reason (financial?), then don't stress it. It would be the best possible situation, but it IS possible to just use the water in the styro fish-boxes, then top up with new de-chlorinated tap water. I have done it both ways. With my 100 gallon, I actually had basically do a 100% water change, because it was a long distance move, and all my fish were fine after that.
Once you've loaded up all your water, fish, deco's, substrate etc... pack uyp whatever equipment is left over. I always take the opportunity to clean the calcium deposits off my heaters at this point. If you aren't keeping this equipment wet, and it's equipment that runs in the water, wip them down. Dead bacteria isn't helpful in a tank and *could* cause a mini-cycle. Same goes for the tanks themselves.
Now for the moving part.
Here's the fun part. If you have the space to do it, leave your fish-boxes hooked up to whatever filters, heaters, air pumps you've already placed in them. This will reduce some stress. otherwise, un-hook any filters, heaters and air pumps that you have running in the fish-boxes, and pack them up. Then tape the fish-boxes shut and move them to your vehicle.
I have a tonne of freaking equipment, so it always takes a minimum of 10 loads to get it all to the truck. So, I turn my truck on, turn the heat on in the cab and place the fish in the front seat/floor area so that the heat doesn't drop. Then I do my wheel-barrow trips back and forth with everything else.
Really try to avoid moving ANYTHING in the tanks. The movement can cause damage. I once cracked a 20 gallon on a move, because the heater that was sitting on the bottom of it, slid and hit the side. What a waste!
Once you're loaded up, take off to the new place.
Whenever I've gotten to the new place, I take the fish-boxes inside asap. I hook them all back up to the heaters, filters and air pumps and shut the lids as much as possible. Then I move on to getting the tanks inside and setting them back up. If I've ever taken more than 5 or more hours between take-down and set-up time, I have done minor minor watrer changes to the fish-boxes, to avoid ammonia.
OMG, did I mention NOT TO FEED YOUR FISH THE DAY BEFORE THE MOVE?!?! DON"T!! Keep that waste to a minimum!
Anyway, set your tanks up, fill them with any tank water that you moved, (not inlcuding the fish-boxes yet), and get the heat up on them. Use warm tap water if you need. Just remember to de-chlorinate! All this moving around, and all these items, and it's possible to forget that detail (I have.. horrible!).
Check your new tap water for any differences (nitrates, chloramine).
You should be ready to go at this point. You've probably already moved your filters and heater and airpumps to the tanks, so leaving your fish alone in those fish-boxes isn't too great of an idea, since they've already been there a number of hours. So move them home! Use the water if you can as well!
Well, I hope I haven't left anything out. And I hope this helps... If you have any questions, don't hesitate!
GOOD LUCK!
Decz.