Choose a bowl:
The first step of course is to choose a fish bowl. Since you plan to accommodate two species inside it, your fish bowl needs to be large enough to provide their needs. The fish needs space to swim around and remain active while the lily will need space for its roots.
The fish bowl should be large enough to hold water more than a quart. The neck of the bowl should not be very narrow because it has to accommodate the plant.
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Choose a lily:
From the local nursery get a peace lily which is mature with a developed root system. The lily will remain above the water but the roots will be dangling inside. However, make sure that these roots do not take up a lot of interior space because the fish needs to move around freely. Another thing to consider is the diameter of the lily. It should be less than the bowl opening so that it can fit in and still allow enough air to enter the bowl for the fish.
Remove the soil from the lily roots and rinse them with water to remove soil particles.
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Set up the system:
Find a plastic cup or tray that fits on the mouth of the bowl. Use a sharp knife to cut a hole in it, large enough to pass through the lily roots. Place the cup/tray over the bowl neck and insert the roots of the lily through the hole.
Fill the bowl with water and place your fish in it. Then top up the bowl with the lily in a way that the roots are dangling in water and the rest is above it. You can make small additional holes in the plastic cup to allow in more air for the fish. You can also add marbles to the bottom of the bowl to make it more appealing. You just created something fantastic for yourself.
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