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Hotwater treatment for bites


Staff member
Moderator (Staff)
Sep 4, 2006
Cape Coral, FL
I have read several reports to use hot water if you are bitten/stung by any saltwater critter, including octopuses so I thought I would report on today's tank cleaning adventure.

I have a flower anemone (not in with my horses or octopus) that I have come to suspect is the cause of a rash that is recurring on my tank cleaning/feeding arm. I have been trying to avoid contact with this gluttonous critter when feeding but didn't succeed while cleaning the tank today. I tried the hot water but it doesn't seem to be effective.

The next tank I cleaned has my dwarf lion who I have had since it was only 2" long and I am never concerned about being stung. Well ... I was not paying close enough attention and sort of ran into her and knew it! Fortunately, the water was still hot in the tap and after about 3 minutes of continueally running hot water over the hand (and remembering barely in time to get my ring off) there was no stinging sensation left from the three place I got tagged and my hands are back to normal (except for the anemone rash on my forearm).

The moral, hot water works for some but not all critter venom and just a quick rinse is not enough to tell.
:shock: yikes, don't use hot water for sea anemone or jellyfish stings - they have nematocysts which will "fire" when exposed to hot water... and cause it to hurt more...

the hot water remedy (as hot as you can stand) works to break down proteins, which are in some venoms (which is why it worked on your lionfish sting).

Sounds like you had a rough day...
Thanks for the additional info as I knew hotwater was not best for some things, just not what things.

Now, do you have a suggestion for the anemone toxin (other than gloves ;>). I don't expect to have many Trundle experiences but still have to deal with my flower anemone on a regular basis. Would vinegar help or hurt (usually vinegar and hotwater are recommended together so I am kind of assuming that is a no as well) or would COLD water be appropriate. It seems I am becoming more sensitive to the anemone and would prefer not to wear gloves (it may be that she is just larger now rather than a sensitivity issue).

I've read hot water works for stingrays, urchins, & crown-of-thorns starfish. too. Is there a way to get rid of nematocysts without setting them off?

I've got 2 references from the 80s described below, but I'd be very interested to hear what reefkeepers and real marine biologists have to say practically...

edit: stupid quick reply combined with user error ate the references.

bottom line: rinse with saltwater, not freshwater ('cause that fires them, too) and use alcohol or vinegar baths for 30mins to kill the stingers, then shave or scrub the area to remove the stingers. But one has a warning that alcohol may actually set them off in "in vitro" studies, but it seems to work better than alcohol in the field. That's from 1983, and the DAN emergency manual from 1989 recommends vinegar.
Vinegar is used for stings from the box jelly in aussie. Stinger stations on the beaches usually contain large bottles of vinegar, the other first aid is to....ahem.....pee on yourself!

The hot water treatment means water near boiling, not hot tapwater it is simply not hot enough. You do run the risk of a nasty scald (but I think that's less painful) The first twice I was bitten we didn't have any hot water so I got to suffer for 3 weeks :sad: the third time we had a new water boiler in the staff room, so I used it and it did help. The pain from the bite decreased quickly (hours) and the pain from the scald in two or three days :biggrin2:...better than 3 weeks though!

My hot water is actually very hot (just short of boiling, definitely enought to burn skin) as I use an on demand system rather than just a hotwater water tank. I did not put it at the scalding point (for long ;>) but as hot as I could stand and kept it RUNNING over the hand in a shallow dish. Hand to hot water was less than 30 seconds and I definitely felt a difference after several minutes then continued the treatment until I could not mentally determine where the stings occurred and then some. I did notice that my hand was completely red to start and then returned to normal color in spite of the hot water. The swelling in my pinky (where I had my ring that almost did not come off) and amost all signs of any sting are gone today (I can find the prick marks and they do have a little sensation if is mess with them but I would not really notice if I was not examining my hand). This may have a lot to do with the quickness of contact, speed to hot water source and the strength of venom. Trundle is a dwarf (unlike my son's Volitan who I have also come in quick contact with but without being stung - fortuanately!) and very likely does not have the most venomous of poisons.

The secondary acidic treatment probably works better for males than females :oops: and is not as easy as keeping a bottle of vinegar if you are wearing a wetsuit :wink: . Vinegar was always something we kept on board (even for sunburn) when I was a kid.
The standard treatment is to flush the area with sea water and then treat with vinegar or methanol. Meat tenderizer also works, but is usually not recommended because some people develop an allergic reaction to it. Personally, I can attest to the effectiveness of vinegar. Last year while diving off the coast of North Queensland, I managed to get a mouth full of blue-bottle tentacles. (No, I was not stupid enought to try to eat one. I was making a difficult exit onto the dive platform of the boat in rough seas and switched from regulator to snorkel. A blue-bottle had become wrapped around my snorkel mouthpiece.) When I reported (read screamed) what had happened, I was given a bottle of vinegar. Rotten apples never tasted so good! I lost some skin on my lips and gums, but it could have been much worse if we did not always carry a bottle of vinegar.

Which Vinegar

haptosquilla :wink: ,

Do you keep apple cider vinegar or distilled white. You mentioned rotten apples so I am assuming the former but I have read differing opinions on which is "better".

Also for anemone "stings" explicitly, would COLD seawater be any more effective?

Lastly, your photographic reputation is legendary but that octo picture goes beyond complements!

I marked the first in my favorites.

It is interesting to note that changing the PH with nematocysts (extreme acid or alkaline) kills them but fresh water (still a PH change) triggers them. I never thought about using baking soda - good old bee sting remedy.

I did try cold (40 degree F) salt water on my forearm to see what it would do. The irritation stopped and the spot does not itch but there is still a slight welt. Next cleaning I will try vinegar. I did move the other flower (that does not sting me - yet) to a location where she can be fed without the difficult contortions but cleaning the tank is still problematic.

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