- 1). Drain the aquarium and clean it out. Remove all turtles, gravel and plant life. If anything is left in the tank, it will not be usable due to small glass shards resulting from the cutting process.
- 2). Locate the area where you want to place the filter inlet. Typically, the hole is located at the half-water level on the rear tank glass.
- 3). Place blue painter's tape on each side of the aquarium glass where you plan to drill the hole. The painter's tape helps to keep shards of glass from scattering.
- 4). Insert a diamond-tipped drill bit into a hand drill and place the drill on the slowest setting possible. The size of the drill bit depends on the size of the plumbing for the filter. The instructions that come with the filter indicate the proper drill size for your application. Do not deviate from the recommendation. If you do, you risk having leaks around the seal between the glass and the plumbing.
- 5). Place the drill plate against the glass and hold it against the glass with one hand. The drill plate keeps the drill bit from sliding around on the glass.
- 6). Place the drill bit against the glass, inside of the drill plate and slowly drill a hole in the glass. Allow the drill bit to cut. Do not push hard on the drill bit. It should take several minutes for the drill to cut through the glass. This is normal.
- 7). Remove the painter's tape from the inside and outside of the aquarium.
- 8). Sweep out the tank with a vacuum cleaner to remove any shards of glass.
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