Aquarium planting grid

After having serious problems to getting grass nearby some other plants growing on a little terrace in my aquarium I got the idea to 3d print a small stackable grid with small walls. Even the fishes loved to pick on the plants to much...

Idea / Concept
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The idea is to put eg grass plants under a grid and push the grid with the plants into the aquarium ground with the flat side up. So the plants will stay under the grid on every ground. After the plant are enough grown together with the