1) Going air pump/filter-less on my opae ula tank since I read they don't like current
2) Need biological filter for bacteria to convert ammonia etc...
3) Need area to grow algae (as feed for opae ula), preferably not on tank walls since it's so unsightly.
Float/attach large filter sponge flat on the surface, below the LED
lights. With the strong light, algae will grow rapidly on the sponge. Less light below so no algae. Increased area for bacteria to colonise. No currents/pumps required.
Reckon this crazy idea would work?