Marshall
Turtle Keeper + CPL(H)
This tip is mainly focused on terrarium care for pet turtles but could be used with any indoor aquarium setup that is freshwater and not hyper-sensitive to temp and ph changes. Do Not! use this system if you have city water as that needs treatment before adding it to the tank. In order to do a rapid water change which is easier on you and less stressful on the turtles you can use the system I use at the rescue for the stand-alone terrariums not plumbed into the re-circulation system. Basically you need a medium to large pond pump that has a flow rate that is roughly equal to your water supply flow rate and a long enough hose to run from the pump output to a drain or directly outdoors. Just connect the hose to the pump and submerge the pump into the tank. Once you turn the pump on to start draining the tank let it get about half drained and then begin adding in new water from your supply and let the new water flow in while pumping out at opposite ends of the tank for about 10 minutes or so and once the water inside looks clear enough then turn the pump off and continue filling up the tank to desired level. This is a basic overview but there is an in-depth description with illustrations on the rescue website in order to not clutter or flood this forum. PS: make sure you use a pre-filter on the pump or be extremely careful not to injure or kill your fish by pulling them into the pumps intake. I usually keep a pencil handy and tap the pumps hose hard every few seconds to cause a vibration that will keep the fish away from the pump.