Reefkeeping Dangers


Contributing Member
I thought it is important to understand some of the potential hazards, some serious, within our systems. On land, there are many plants and animals that are poisonous, so why should the ocean be any different? We wouldn't keep a poisonous snake without learning about it first (I would hope anyway :rolleyes: ). We cannot rely on the LFS to inform us about the dangers of the purchase we are about to make (assuming they are aware of them).

Zoanthids: contain palytoxin. This can be fatal if ingested. Here are a few threads about the dangers of palytoxin:
* Zoanthids, are they toxic?

*Emergency with Zoanthids

*Pregnancy and the Reef Aquarium - this link also contains other helpful information

Mycobacterium marinum - this is something else to be aware of. Just a side note: this link contains a few pictures that might bother those that are a bit squeamish (pictures are of an infected finger).
* Mycobacterium marinum: The fish disease you could catch

Fish: Lionfish - each spine has an elongated poison gland, which contains a neurotoxin. Ladywildlife's Lionfish Page

Rabbitfish also have venomous spines

There are also bristleworms...although nothing like the danger of a lionfish, the bristles can get in your skin and be irritating.



Some types of nudibranches, too. I'm still trying to find the information for this one, though.

What can we do? Well, the answer is pretty easy. First, don't panic about is just for your information. How many have gone years without thinking twice of having their hands in the tank, and nothing happened? The point is to educate yourself. Use common sense when working in your seems easy enough, right? Wearing gloves is a start. Try not to put your hands in the tank if you have any type of open wound. Don't touch your eyes, nose, or mouth until you've washed with soap. If you are Pregnant, Nursing, or Immune Compromised, then use caution and talk with your physician about any concerns. Keep a histamine blocker (such as Benadryl) on hand in case of a reaction. Many people have allergic reactions to corals in the same manner as bee stings. Anaphylactic shock is nothing to mess around with.

I hope this thread informed you of a few of the hazards we work with. Please, add any extra information you have. I, by no means, am an expert.

This is for informational purposes is by no means to be used to diagnose or treat symptoms....please ask a physician for serious concerns about anything that you have read
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Active Member
First of all, NaH2O.....KARMA TO YOU!!!

Secondly, I want to reitterate that Reef Sanctuary is not giving medical advice in any way, shape, nor form and cannot be held liable for any advice you choose to use based on this thread. If you have a medical concern, contact your doctor or emergency room.

This list is not all-inclusive. The fact that an animal in your tank does NOT appear on this list, does not mean it is not a possible hazard.

Reef Sanctuary likes for it's members to be informed and SAFE!!! For new beginners, don't let this thread worry you. Just follow the good habits listed in this thread.

Here are some additional resources including toxic nudibranchs, pufferfish, soapfish, etc.

Toxins for Self Defense

Don't Squish Nudibranchs with your fingers

Cone Snail Toxins

5 Poisonous Fish Families

Hazardous Marine Life and First Aid

It's just a Scratch, or is it? (Wound Management)

All Stings Considered

If your doctor has prescribed Epi-Pens to you for the treatment of bee stings, make sure it is not kept beyond it's expiration date.

Starting siphons by sucking on the hose is NOT a good practice. I'm not saying I haven't done it----I'm saying it isn't a good practice. (Fluval and Hagen both make siphon starter bulbs that are very inexpensive).


Contributing Member
Oh my gosh! Thanks, Curt, for the supplemental links! I completely forgot about the cone snail. Great idea about the Epi-pens, too. Karma your way.


Fish Addict
Excellent Nikki, karma to you for starting this thread! It should (if it hasn't already) be a sticky.

Craig Manoukian

Well-Known Member
Why am I not dead!:eek:

I am the poster child for what you shouldn't do in a reef tank.:eek: I'm running with scissors, I'm running with scissors!

:) :D :cool: ;) :p :smirk:

Great stuff and I will be more careful, I poromise!


Active Member
Craig said:

"I am the poster child for what you shouldn't do in a reef tank. I'm running with scissors, I'm running with scissors!"

That makes 2 of us.

Nikki great thread, one that could save a life.


Contributing Member
"NO RUNNING WITH SCISSORS!!! Walk, please, and have the pointy end down". Whew...the mom in me had to come out, sorry.

Craig Manoukian

Well-Known Member
Originally posted by Playa
Craig said:

"I am the poster child for what you shouldn't do in a reef tank. I'm running with scissors, I'm running with scissors!"

That makes 2 of us.

We're twins?:confused:

:) :D :cool: ;) :p :smirk:


Well-Known Member
Great thread.

From personal experience I would like to say if you even suspect that something in your tank is affecting you, check it out with a doctor. Use as many precautions as you can when dealing with your tank, even though you don't show any allerges today doesn't mean you'll be fine tomorrow. I wasn't allergic to very many things before I got my tank, but within a year I developed hypersensitivities and then allergies to substances in my tank.

A little precaution goes a long way, this isn't a toy we are dealing with, but highly evolved animals who have survived on this planet longer then we have!


Active Member
Excellent posts everyone. What Cougra posts is very true. I got stung by bees all of the time when I was little and it was no big deal. I have since developed hypersensitivities to a lot of substances and I actually have scars on my arms from touching my corals. I can also die from a bee sting now and that is why I know what an Epi-Pen is.

I will provide more info later. However, there was another thread with possible mantis shrimp in them.

Even though I keep a mantis in a nano tank, I do NOT put my hands into it. Even if they don't break your fingers, smashers also have barbs as well. The spearers obviously have barbs. You can get a nasty infection from a strike from either type.

Like I said....more info will come later. However, I wanted this warning out there.


Contributing Member
Great info all :thumbup:
Along with the lions, rabbits, stone, and soap fish people should also remember that the common coral catfish has a powerful sting.
Here is a link with some info that may help

Note this part:
“If it is necessary for you to handle your Coral Catfish, you should use caution; spines located to the front of the pectoral and dorsal fins are venomous and will cause a painful injury. If for some reason it is necessary for you to reach into an aquarium containing Coral Catfish, use caution and be aware of the fish's position at all times.”


Excellent thread, nikki!

The information about the development of allergies is correct- allergic reactions don't happen the first time someone is exposed to the allergen- it takes multiple exposures for your body to develop histamines against the allergen (histamines cause allergic symptoms), and the more times you are exposed to a possible irritant, the worse your reaction could get. So.... always use gloves! Just because something didn't bother you the first few times you touched it, doesn't mean it never will!