The substrate need to be gentle and in case you elect to put rocks be sure They can be sleek river rocks. The neon tetra prefers to reside in a intensely planted tank. There should be subdued lighting that reaches Within the waters and lots of hiding spaces. Graphic Editorial https://medium.com/@FishAquariumOnline/4-facts-about-maintaining-your-aquarium-by-a-fish-tank-cleaner-95421e6c2baa