Bare bottom (no substrate)

Also known as: Bare bottom, Glass bottom

Properties

pH effectnot applicable
KH (carbonate hardness)not applicable
GH (general hardness)not applicable
Nutrient loadnone
Ammonia release initiallyNo
Longevityindefinite
Cost tierfree / DIY

How it affects the tank

  • Maximum visibility of detritus: anything that drops to the bottom is obvious and easy to siphon, making this the choice for breeders, shrimp colonies, and species that benefit from extreme cleanliness (discus, fry-raising tanks)
  • Forces plant choice toward epiphytes (anubias, java fern, mosses) mounted on hardscape, or floating plants
  • No anaerobic zones to worry about; no substrate to vacuum during water changes
  • Some fish (cory cats, kuhli loaches, eels) dislike a bare bottom and become reclusive without a soft substrate to forage on

Care notes

Standard practice in discus breeding tanks, shrimp colony setups, and quarantine tanks. Aesthetically divisive; works visually with planted hardscape (wood + epiphytes + moss) but feels clinical with just fish. Reflection from the tank floor can stress some species: a thin sand bed in a far corner or a mat of moss helps.

Plants that work in bare bottom (no substrate)

21 aquarium plants in the catalog list this substrate as compatible.

Sources

Data drawn from: discus-keeping-references, shrimp-keeping-references. Last verified 2026-05-13.

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Further reading