Longhorn Cowfish Experience


New member
This is not a question but rather an anecdote of my experience with a Cowfish. One thing that I first check for a fish is if they are reef safe. I searched online and watch videos. There isn't much info beyond these:

- They are reef safe except they will kill your Feather Dusters and Skunk Shrimps
- They have toxins that can kill your tank
- They grow big quickly and hard to take care of

Here's what I learned so far
- They are not reef safe. My cowfish nibbled my perfectly healthy Acan. He managed to reduce a 110% sized acan to 50%. They are now recovering at 80%.
- My Cowfish plucked one of the the polpys of my toadstool really hard. The toadstool surprisingly didn't budge
- He got bullied by a Tang and forced him on the corner. He got harassed by a bunch of mollies. At the end of the day he is perfectly fine and got along with them. It's been a montj and no one died.
- When I transferred him out of the main tank because of his nibbling behavior, he showed extreme stress by flapping his tail. I was worried he would release toxins. It's been two weeks and my tank is still good.
- He is still small. I don't see him growing quickly as I would anticipate
- He is a PIG. He eats Hikari pellets, Omega wafers, frozen Mysis, freeze Mysis (and corals). He did nibble at my feather duster which I was fine but he prefers my Acans!
- He poops a lot of spaghetti like black strands. Again A LOT
- When cleaning the aquarium watch out for your skin. He will at times nip you. The initial ones were nothing. It just surprises you. However there were cases were he did nipped hard and cause my backhand skin to bleed. It hurts when he wants to.
- He has zero interest in my Skunks (maybe for now)
- ICH magnet

Now the good stuff
- He likes to stay in front of the aquarium which makes him more visible
- Once he is relaxed and recognizes you, he will move around the tank, go to the surface and do backward swim and spit water. It's entertaining to watch
- No food is wasted
- He is easy to catch and you can touch him
- He likes GSPs. He likes to roll and sleep on them.

My recommendation:
- If you are gonna get one, don't mix with any corals
- He is easy to take care of because he can be fed with almost anything
- Clean out those poops
- He is very peaceful with the other fishes
- Go with TTM to clear up ICH


New member
yeah i have had a couple over the past 5 years. my favourite fish. i fed them well so they never touched corals, but that probably just me getting lucky. love the personality though. :)

top shelf

New member
How did he reduce your 110% Acan to 50%?

Very interested in how you had a 110% sized anything.

If I had to take a guess he is using that as a reference for growth. As in it grew 10% from its original size so for the sake of simplicity he said he had a 110% acan that is now 50%. As for how, by eating it.

No worries accel, I think most understood what you meant.


New member
My old time fav fish in my tank.You have explained the longhorn to the letter mate because mine is very close to that but does not eat any coral in 2 years. he has doubled in size but over 2 years and yes there is nothing he does not eat but i feed my fish quite well so i guess no need to eat crappy tasting corals lol.he does love eating nori from the clip aslong as my powder blue lets him so quite funny to watch.


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