Usually, not in the same way as a fish pond. A pondless waterfall does not have a standing pond stocked with fish, so its design priorities are water storage, circulation, debris control, and pump access rather than managing a fish-pond biological load.
That does not make the feature maintenance-free. Leaves, sediment, soil, algae, and other debris can still reduce flow or reach the pump area. The gravel cover and reservoir layout are part of the system design, so they should be installed and maintained according to current instructions.
What should I check?
Keep leaves and loose debris out of the basin and stream. Watch for low water, reduced flow, pooling, unusual pump noise, or water escaping at the edges. Turn off power before inspecting the pump or reservoir. Clean only the components and surfaces that the current instructions allow you to service.
What if fish are present?
If a feature has a permanent standing area for fish, it may no longer be functioning as a simple pondless waterfall. Fish change the filtration, oxygen, water-quality, and maintenance requirements. Treat that as a pond-design question rather than assuming a pondless setup is enough.
FAQ
Does gravel replace every kind of filter?
No. Gravel and the reservoir layout can support debris management in a pondless design, but they do not make every material arrangement suitable or eliminate cleaning.
Can I use pond filtration equipment in a pondless feature?
Only when the equipment and layout are compatible with the feature. Follow the current product instructions instead of adding a filter by guesswork.