Pleco quite often have their tails outside the cave, waving back and forth to keep the water fresh inside the cave.
Tile stores sell 3" x 6" tiles. Ask them to cut two in half for you. They have tile cutters and it only takes a few seconds. Find a single 1.5" x 1.5" or 2" x 2" small tile to plug one end. Even if you have to purchase three of the tiles, you should still have only about a $1 invested.
Silicone or Gorilla glue those pieces into a box. Rough sides inside.
Silicone or Gorilla glue the small tile to the end of the box you made.
Let cure for a couple of days.
Ima try this. Thanks!
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