Stripefin poacher

Where they come from

Stripefin poachers are cool-water bottom fish from the eastern Pacific, mostly off California down into Baja. You find them parked on sand and shell hash, sometimes pretty deep, where the light is dim and the water stays cold year-round.

Setting up their tank

A chiller is non-negotiable. Mine did best between 52-58 F (11-14 C). Warmer than 60 and they start breathing fast and go off food. I ran a 50-gallon with a big footprint, lots of open sand, and just a low rubble ridge to lean against. Keep lighting dim.

• Tank size: 40 gallons minimum with a wide footprint. Bigger is always steadier for coldwater.
• Filtration: strong skimmer, high aeration. Cold water holds more oxygen, but a chiller failure happens fast.
• Flow: gentle along the bottom. They hate getting blasted. I angled returns to move waste without tumbling them.
• Substrate: fine sand mixed with some shell. They like to sit and scoot, not sink.
• Lighting: low to moderate. Blue-leaning spectrum looks natural and keeps them comfortable.
• Lid: tight cover. They rarely jump, but coldwater setups are pricey to heat or cool, so keep evaporation down.
• Handling: use a specimen container, not a net. Their bony plates snag and mouths abrade easily.

Skip stinging anemones and big urchins. Poachers are slow and clumsy. I keep macroalgae and sponges instead for a calmer feel.

What to feed them

They pick tiny crustaceans and worms in the wild. Most new arrivals ignore pellets and flake. Expect to start with live foods and then wean to frozen.

• Live starters that worked for me: rinsed live blackworms (in saltwater right before feeding), live mysids, amphipods from a refugium, small grass shrimp.
• Frozen options once they catch on: PE mysis, finely chopped clam or shrimp, Nutramar ova, chopped bloodworms (not marine, but some take them).
• Target feeding: turn off flow, use a pipette or turkey baster, and place food right in front of the fish on a small ceramic feeding tile.

Feed small amounts 2-3 times a day at first. They are slow, so give them time. Mine took about two weeks to go from live mysids to frozen mysis reliably. Vitamin soaking (like Selcon) helped during the weaning phase.

How they behave and who they get along with

Stripefin poachers are mellow, slow, and oddly charming. They sit, shuffle, and do little bursts to pounce on food. They ignore most fish and inverts, but they cannot compete with quick feeders.

• Good company: very calm coldwater gobies, small sculpins that are not aggressive feeders, snails, small brittle stars, and non-stinging filter feeders.
• Risky: big hermit crabs (they pick at the poacher), anemones, fast fish like surfperches or juvenile rockfish, anything that lunges at food.
• With conspecifics: you can keep more than one if space and food allow. They mostly ignore each other, but give several resting spots so no one gets crowded.

Breeding tips

I have not seen a confirmed home spawn for this species. In the wild they likely have seasonal cues and a larval stage that would need planktonic foods. If you happen to keep a pair, you could try mimicking a cool winter period followed by heavier feeding and a slight light increase, but do not expect results. If anything happens, document it and share with the coldwater community.

Common problems to watch for

• Heat stress: rapid breathing, listlessness, refusing food. Check your chiller, clean its filter, and verify flow through the heat exchanger.
• Starvation: a pinched-in belly line behind the head means they are not getting enough. Increase live foods and isolate during feeding.
• Collection wear: scrapes on the snout and plates can get infected. Quarantine new fish and keep the bottom clean. I had good outcomes with a broad-spectrum antibiotic in QT when needed.
• Flukes or other parasites: flashing or excess mucus. Praziquantel works well. Go easy with copper on oddball coldwater fish.
• Net damage: mouths and fins get torn in mesh. Move them in a container instead.
• Overbright tanks: constant hiding and no feeding response under intense lights. Dim it down and add shaded areas.