The Cleanup Crew Prescription: Match the Animal to the Problem

Somebody sold you a “40 piece cleanup crew for a 20 gallon tank.” Six weeks later most of them are dead, the glass is still dirty, and you are dosing to fix a nitrate problem the dead snails caused.

The standard cleanup crew pack is sold by tank size. Tank size is the wrong variable. What matters is how much food is actually in there, and a new tank with a light dusting of diatoms does not contain enough food for forty animals. Most of them starve, and starving snails foul the water they were bought to clean.

This page is the other way round. Start with the problem you can see, and buy the animal that eats it.

Match the animal to the problem

How many, honestly

Rather than a per-gallon rule, use what you can see.

• A tank under three months old with light diatoms. Five to ten grazing snails is plenty. Add more when there is visibly more to eat, not before.
• An established tank with a weekly glass wipe. Roughly one grazing snail per 5 gallons is a working starting point, adjusted by how fast the glass films over.
• A tank with a real algae problem. Do not buy your way out of it. Nutrients, flow and light come first. A crew maintains a clean tank. It does not clean a dirty one.
• Hermits. Fewer than you think. They knock frags over and they will kill a snail for its shell if you do not leave empty shells around.

The animals, and what each one is actually for

Fresh Florida Keys Astrea Snails — flat surfaces. Glass, rock faces, the film you wipe every week. They do not knock frags over. They are poor at righting themselves if they fall on sand, so flip any you find upside down. From $19.99.

Banded Trochus Snail — the same job as astrea and better at getting back up when they fall. Good in tanks with a deep sand bed. $31.49.

Tiger Turbo Snail — larger, eats more, clears heavier film faster. Big enough to bulldoze a loose frag, so glue things down. $26.99.

Nassarius Snail — a sand-bed scavenger, not a grazer. They stay buried and come up when food hits the sand. They will not touch algae, and buying them for algae is the most common mistake on this list. $23.49.

Green Emerald Crab — the only common animal that reliably eats bubble algae. One per 30 gallons. More than that and they start competing, and a hungry emerald will pick at coral. $9.99.

Blue Legged Hermit Crab — detritus and leftover food. Small, cheap, effective in the rockwork. Leave spare shells in the tank or they will take one off a snail. $10.99.

Scarlet Reef Hermit Crab — better behaved than blue legs and less likely to bother snails, at a higher price. $35.49.

Peppermint Shrimp — the aiptasia option. Some individuals eat it and some never do. Nobody can promise you which one you are getting, and any shop that does is guessing.

What we will tell you not to buy

If you message us with a photo of hair algae and ask which snail fixes it, the answer is usually none of them, and the honest advice is to wait. Buying animals to eat a nutrient problem gets you a nutrient problem plus dead animals. We would rather lose the sale than sell you that.

If your tank has been running under a month, buy almost nothing. There is not enough food in it yet. Come back when the glass films over in a week.

Where these come from

Most of our cleanup crew is collected in the Florida Keys, which means a short trip in a bag rather than a week in the international chain. Animals that spend less time in transit arrive with more left in the tank. That difference is the whole subject of why the cheapest coral costs the most, and it applies to inverts as much as to coral.

The Underwater Gardener grows aquacultured corals in Key West, Florida (FL Aquaculture Certificate #AQ0254072). Livestock ships UPS Overnight every Tuesday and Wednesday. Visit the shop at 2816 N Roosevelt Blvd, Key West.