With the aquarium plumbing completed, it was time to test the system by adding water. This was done by using a garden hose to fill the tank with fresh tap water.
Why did we do it this way, you ask? Because it would have been costly to buy the sheer volume of RO water needed, over 100 gallons, as well as problematic to haul it from the pet store to the house.
Once the aquarium and sump were filled to the correct levels, the pump was plugged in, the water output flow was adjusted using the ball-valve, and the system was left running until the next day. During this test run time every hose connection and tank seam was closely inspected for leaks, and the heater was placed in the sump and plugged in.