You have Green Hair Algae taking over your rocks. You have Bubble Algae popping up in the corners.
You look at the price of a Yellow Tang (the classic algae eater), and it is RM200 – RM400 because of the Hawaii export ban.
You need a worker that is cheaper, hardier, and hungrier.
Meet the Foxface Lo (Siganus vulpinus).
With its bright yellow body and black-and-white “badger” face, it looks unique. But we don’t keep it just for looks. We keep it because it is a lawnmower with fins. Here is why every reef tank needs a Fox.
1. The “Cow” of the Sea
The Foxface is a herbivore. It grazes constantly.
- The Menu: It eats almost every type of nuisance algae, including the dreaded Valonia (Bubble Algae) and Bryopsis (Hair Algae) that most other fish ignore.
- The Appetite: Unlike Tangs that can be picky, a Foxface will usually clear a tank of algae within a few weeks. It saves you hours of scrubbing.
2. The “Camouflage” Scare
This is the #1 question new owners ask on forums: “My Foxface turned black and is lying in the corner! Is it dead?”
No.
The Foxface has an incredible ability to change color.
- Sleeping Mode: When the lights go out, it turns a mottled brown/grey color to blend in with the rocks. It looks like a rotting leaf.
- Stress Mode: If it gets scared, it also turns brown and spikes its fins.
- The Fix: Turn the lights on. Within 5 minutes, it will turn bright yellow again. Do not flush it!
3. The Venom Warning
It is called a “Rabbitfish” because of its peaceful, grazing face.
But it carries a hidden weapon. The spines on its dorsal (top) and anal (bottom) fins are venomous.
- Is it aggressive? No. It will never attack you.
- The Risk: The danger happens during tank maintenance. If you are scrubbing a rock and accidentally corner the fish, it might panic and spike you.
- The Sting: It feels like a bee sting but much worse. It causes intense throbbing pain. If you get stung, run your hand under the hottest water you can stand (heat breaks down the protein-based venom).
4. Tank Mates: The Peacekeeper
The Foxface is one of the most peaceful large fish you can own.
- Bullies: It gets along with aggressive fish (like Triggers or Tangs) because… well, it has poisonous spikes. The bullies know to leave it alone.
- Reef Safe: It is generally 100% reef safe, though a hungry Foxface might nip at some soft corals (Zoanthids) if there is absolutely no algae or Nori to eat. Keep them fed!
5. Tank Size
These fish grow relatively large—up to 7-8 inches (20cm).
They are active swimmers. You need a standard 4-foot tank (75 gallons) minimum. Do not put a Foxface in a 2-foot cube; it will get stressed, turn brown, and stop eating algae.
If you want the bright yellow color of a Tang without the high price tag (or the “Ich Magnet” health issues), the Foxface is the winner.
It works hard, it looks cool, and it takes care of itself. Just remember to wear gloves when you clean the tank!
