Doing a water change consists of (a)preparing the new saltwater, (b)draining the dirty water and (c)replacing it with the new saltwater.
(A) Preparing Saltwater
Fill 30 gallon trash can with filtered water a day or two before the water change.
Heat the water to 78 degrees F before adding salt.
Scoop salt into the trash can. 1/2 cup per gallon
Stir the water with a stick
When the salt is completely dissolved, test the water with the hydrometer
*If there is too much salt, add more fresh water*If there is not enough salt, add more salt*It's usually easiest if you err on the side of too little when you start the process.
(B) Draining Old Water
Place a bucket next to the fish tank
Say "Alexa, I am draining the tank"
Alexa will then turn off the skimmer and powerheads
Take the tube with a squishy ball and place the end without the ball into the fish tank
Squeeze the ball to create some suction (make sure the ball end is pointing up)
When water starts coming through, put the ball end of the tube into the bucket
Allow the water to drain about 1/3 of the way (you will need to empty the bucket several times to drain enough water)
(C) Filling With New Water
Take the tube attached to the pump in the 30 gallon trash can and point it into the tank
If you point it down on top of a powerhead, it won't kick up the sand as much
Say "Alexa, fill the tank"
Wait for the tank to be filled
When the tank is mostly filled say "Alexa, stop filling the tank"