Bristlenose catfish (Ancistrus species, also called bristlenose plecos) are mostly plant and algae eaters. Feed them algae wafers, blanched vegetables such as zucchini and cucumber, and driftwood to rasp on, plus an occasional protein treat. Feed in the evening, because they are most active at night.
What bristlenose catfish eat
- Algae wafers or sinking pellets. The staple food. Choose one made for plecos with plant ingredients.
- Blanched vegetables. Zucchini, cucumber, peas (shelled), spinach, kale and sweet potato are all good choices. Blanch hard vegetables for a minute or two to soften them.
- Driftwood. Bristlenose rasp on wood for fiber, which supports digestion. Provide a piece of aquarium-safe driftwood.
- Natural algae. They graze on algae growing on glass, rocks and decor.
- Occasional protein. Sinking pellets, frozen bloodworms or brine shrimp now and then. Do not overdo it.
How often and how much to feed
Feed once a day, in the evening, after the lights go off or are dimmed. Offer one algae wafer per one to two fish, and a small slice of vegetable a few times a week. If the wafer is gone within a few hours and the fish still look slim, offer a bit more.
Remove uneaten vegetables after 12 to 24 hours, so they do not foul the water.
Tips for a healthy bristlenose
- Make sure the fish actually reach food. Fast tank mates can eat everything first.
- Check the belly. A rounded, full belly is normal. A sunken belly means underfeeding.
- Maintain good water quality, with regular partial water changes.
- Provide caves or tubes. Bristlenose are shy and use hiding spots.
Foods to avoid
- Large amounts of high-protein foods
- Bread, cooked human food and anything seasoned
- Spoiled vegetables left to rot in the tank
Frequently asked questions
Do bristlenose catfish eat algae?
Yes, they graze on soft algae, but algae alone is rarely enough. Feed wafers and vegetables too.
Will bristlenose eat my plants?
They normally leave healthy live plants alone, but they can nibble on soft or decaying leaves, especially if underfed.
Why does my bristlenose rasp on wood?
Wood provides fiber and gives them something to graze on. Keep driftwood in the tank.
Bottom Line
Feed bristlenose catfish a daily algae wafer, fresh blanched vegetables several times a week and driftwood to graze on. Feed in the evening, clear leftovers and ask an aquarium vet or experienced fish store if your fish looks thin or is not eating.
Related reading: Bristlenose Pleco Food List
