Hair algae, bubble algae, Aiptasia, cyano — what eats what, and why husbandry beats a bigger cleanup crew.
6 questions, answered honestly and water-first.
Grazers help — certain tangs, turbo and trochus snails, and a tuxedo urchin will mow it — but a cleanup crew can't out-eat an underlying nutrient problem. Cut the fuel (nitrate and phosphate) with water changes and feeding control, and let the grazers keep the tidied rock clean.
An emerald crab is the usual pick — but be honest about it: it eats bubble algae mainly when hungry and can turn to corals or snails when it isn't, so keep it lean and remove big bubbles by hand (without popping them in the tank). It's a help, not a guarantee.
Peppermint shrimp (the real Lysmata wurdemanni) will eat Aiptasia — but identification matters, they may ignore it if well-fed, and look-alike species won't touch it. For reliable control, spot-treat the anemones with a dedicated product. Don't scrape them off, which just spreads them.
Algae is a symptom of nutrients plus light in an immature tank. A new tank's "ugly stage" passes on its own; a persistent bloom means excess nitrate/phosphate (overfeeding, tap water, loose stocking) or too long a photoperiod. Fix the husbandry first — a bigger cleanup crew alone won't do it.
Right-size it to your tank — a mix of grazing snails, a few scavengers, and maybe a hermit or two. Overstocking a crew just starves it, so start small and add as needed. Match the crew to your tank's real problems, not a snail-per-gallon myth.
That red, purple or brown slimy film is cyanobacteria — a bacteria, not a true algae — and it blooms where nutrients are high and flow is low. Improve flow, tidy up detritus, and bring nutrients into range; it usually recedes as the tank matures and balances.
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Short answers from the Coralkin team — kind, general guidance, not a diagnosis. When something looks wrong, test your water first, and for a serious case ask an experienced reefer or an aquatic vet.
