I have used semi aquatic (pond type) plants for years. But many need a kind of shelf to be only half submerged.
Papyrus is one of my favorite, along with terrestrial type hanging with roots in the water. And i maintain a very low nitrate level with them.
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above, terrestrial plants on my main tank to the left, on the far right Papyrus in the sump.
Below submerged papyrus roots, I doubt oscars would eat them, they are like paper, or cardboard.
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another shot of a tank using Papyrus, I find them attractive
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These work in tanks of of @20" tall resting on the substrate, much deeper tanks may require a shelf.
Below my normal nitrate levels, using these plants as nitrate sponges.
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Below terrestrial plants on my main tankas as of a few days ago
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