A worker fish needs a workplace
The siamese algae eater comes from flowing Southeast Asian streams, and its whole body is built for two jobs: grazing film off surfaces and holding station in moving water. It is one of the most active fish in a community tank when both jobs exist — and one of the most restless when they do not. Enrichment here is less about toys and more about keeping its workplace stocked and its river running.
Leave it something to graze
Resist the urge to polish the tank spotless. A film of soft algae on the back glass, on driftwood and on flat stones is this fish's daily work, and it will methodically comb those surfaces for hours. Position a broad, flat rock and a piece of wood where light reaches them so the film renews itself. You can confirm you have the true species while you watch it work: the black stripe runs unbroken through the tail fin itself, not stopping at the tail's base as it does in the look-alike flying fox.
Resting perches and a current lane
Between grazing shifts, a siamese algae eater famously parks itself — propped upright on its lower fins on a broad leaf, a flat stone or the wood, watching the tank go by. Broad-leafed plants at mid-height are therefore furniture, not decoration, and a fish with no perch spends its rest time pressed awkwardly against the glass. At the other extreme, aim the filter outflow to create a defined lane of flow along the tank's length: this fish will cruise it, turn and cruise back, the way it would work a stream. Choose the longest tank you can, and keep a tight lid on it — startled or exploring algae eaters jump.
When the algae runs out, forage must not
A tank can be grazed clean, and a hungry algae eater with nothing to work on may start rasping at plant leaves or pestering slow tankmates for their slime coat. Prevent it by treating supplementary food as enrichment: clip blanched zucchini or a leaf of greens in a new spot every couple of days, break wafers across several surfaces rather than one pile, and let small frozen foods drift in the current lane now and then. Scatter and relocate, so the fish keeps searching the tank instead of waiting at one feeding point.
Company, and the age curve
Young siamese algae eaters shoal loosely and graze in company; adults grow large, more territorial with similar-shaped fish, and a little lazier — which is exactly when the current lane and scatter-feeding matter most. House one per tank unless the tank is very large, keep it away from slow, broad-bodied tankmates it might bother, and read a sudden drop in grazing as a water-quality flag worth testing for. Keep the grazing rota shared in KinsLe, where Care Teams can assign vegetable clips, wafer scatter-feeds and lid checks to whoever is feeding that day, each job closed out with a timestamp.