Seatorch Aquarium WK Series Cleanable Water Tank Easy Setup, Food-Grade Plastic, Ideal for Tank Water Prep

Instructions:

① Use a wrench to turn counterclockwise to open the lid.
② Fill the refill tank with fresh water or RO water.
③ Use a wrench to turn clockwise to secure the lid.
④ Place the refill tank upside down on the aquarium glass and tighten the screws.