Being cheap by nature, I found it was much less expensive to purchase bare tanks rather than
complete setups (tank, lights, hood). Iíd buy a bare 55-gallon tank and use
a standard fluorescent shop light fixture. However, I still needed an inexpensive tank cover
that would allow enough light to penetrate for good plant growth and be easily customized
to allow cut outs for heater, filters and other equipment.
Several years ago when I moved into a new house, I found half a sheet of prismatic
lens material. These 2 feet by 4 feet sheets are used as the lenses for fluorescent
fixtures in drop ceilings. No doubt youíve seen them before and havenít given
them a thought. I found that they make excellent and cheap tank covers and are
fairly easy to cut and customize. You can find the material in home and building
supply stores such as Home Depot and Menards. The lens material is usually located
adjacent to the ceiling tiles. Building supply stores sell several styles of
lenses. You want to find clear material with tiny peaks and valleys (see Figure
1). This material is commonly available in two grades; a basic grade and a deluxe
unbreakable grade. Buy the cheaper material... I have found that the deluxe
unbreakable material curls over time and is harder to work. I have spent as
little as $2.00 for an entire sheet. If you donít have to make a lot of covers,
you can often buy a broken sheet for much less. By the way, youíll find eggcrate
material in the same location so you can pick up some on the same trip to keep
your cichlids from killing each other.
Each 2 feet by 4 feet sheet is enough to create covers for two 55ís or four 20-gallon
tanks. You will need the following to create covers of your own:
- Sharp utility knife or acrylic cutter (see Figure 2)
- Metal square or T-square
- Work gloves
- Fine-point permanent marker
- Diagonal cutters or needle nose pliers
- Fine Sandpaper
- Hole saw and electric drill (optional)
Note: Like any other project involving sharp tools, there is a risk of injury. Please use care in
following these instructions and wear protective eyewear. This is a project for adults.
Making Your Own Tank Covers
Follow these steps and youíll have tank covers in no time:
- Measure the inside frame of your tank and subtract 1/8" from both the horizontal
and vertical dimension.
- Place the plastic sheet flat side up on a hard surface like a large piece of plywood.
- Use the ruler to carefully measure across the shortest dimension of the sheet (see Figure 3). Place a small dot with permanent
- Look carefully at the sheet and observe the pattern of the sheet.
You will need to cut directly across the end points of the diamond pattern to
avoid breaking the sheet when you cut it. This means you may need to adjust
your cut slightly.
- Lay the square on the sheet at your cutting point and make sure that everything is lined up to make a good cut.
- Hold the square down firmly and score the sheet repeatedly with the utility knife (or acrylic
cutter). When you feel the knife start catching in the material (penetrating
the other side), youíve done enough.
- Grab the sheet and carefully flex it against a hard edge (like the edge of table) and the sheet should snap cleanly.
- You may need to use the sandpaper to clean up the edge.
- If you find that the cover is a too big to fit well, you can use the square and utility knife
to score as little as 1/8" along one of the edges. Then, use the diagonal cutters
or needle nose pliers to nip off a small amount at a time.
- Follow the same steps to cut along the other dimension of the cover.