Somewhere around here is someone who made a neat little "water caddy" w attached pump I believe using a small hand truck and 2 plastic jugs.. Sorry, best I can do............I'm trying to figure out the fastest way to do water change while kept stress of the fish at minimum. I have discus tank in my 75G tank and it has been taking a long time to do a 60% water change. I have been using a 5G bucket in a bath tub to hold tap water, then add couple drops of Prime into the bucket and stir the water using a fish net. Then I use a water pump to pump the water into the fish tank. So I repeat these steps 8 times (40G of water).
Other than expensive.. like this: