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What is the minimum time in formaline?


Staff member
Moderator (Staff)
Sep 4, 2006
Cape Coral, FL
I am preserving Trapper in Formaline but am not sure how long to "fix" her in the formaldehyde before flushing the chemical and replacing the original preservative with alcohol.

Of interest. When I took Trapper out of the tank (within two hours of death) she was limp and jelly like, so much so that I was concerned about the success of preserving her. After an hour in the Formaline, she had stiffened, was plumped out and was rubbery.
Trapper will go to a child to be displayed in a sealed wall hanging container. Alcohol is the safest preservative that has been recommended. It is also Steve O'Shea's final preservative of choice for large squid. Do you have another suggestion?
No, i have nothing else, I preserve all of my specemins in Alcohol, its just an issue. Also my last post seemed to have come from the department of redundancy department, sorry.
dwhatley;96056 said:
I am preserving Trapper in Formaline but am not sure how long to "fix" her in the formaldehyde before flushing the chemical and replacing the original preservative with alcohol.


10 days in formalin (note it should be buffered so the Ph is neutral). Large specimens should be injected with formalin as well so that the internal organs do not decompose before the formalin has time to penetrate...Then store in alcohol. The formalin and alcohol will leach out all the colour eventually (as will exposure to u/v). The best method of preservation for cephalopods is Plastination - resulting in a dry, non-fading specimen which can be kept on a shelf rather than in liquid preservative.
Alcohol is all you really need for an octo of that size. I use them on larger squids and they kept for years.

heres some my work =)


Ive tried to articulate an octopus before, but as you mentioned, they are so limp when dead, its really hard to make a controlled form.
Looks like you are starting your own church:wink:

I tried positioning Trapper with a stick but waited too late (15 minutes or so) so her arms aren't perfect but I think she will still display well. I am not really concerned about loosing the red (she had started loosing patterning before she died) but will she turn yellow instead of white? More of a curiosity than anything of real concern since I will finish the preservation with the alcohol in any case. I want to keep this simple but don't want the formaline as the final preservative.

I notice you had handling instructions but nothing about shipping. The container I will use will not be the final one so it won't be sealed. Any suggestions on how to immobilize Trapper for the trip (USPS)? I know foam rubber won't do well but was thinking about bubble wrap if it won't become sticky in the alcohol.

I had planned to reread Steve's preservation guideline before I started the procedure (he mentions injecting the organs) but felt rushed when she actually died because she was so jelly like. I did go back and read the part about injecting and buffering but it was really too late. The formaline I have is already diluted but I don't know the PH. I should test it if I ever plan to do this again but I bought it (mail order) not knowing it was 10 x stronger than what I usually use (discovered before use fortunately). I purchased the weaker brand for use on live fish (seahorses) because I was uncomfortable properly diluting this stuff and really don't like formaldahyde at all :hmm:. Needless to say, preserving Trapper gave me a way to get rid of most of it without just dumping it (which was also a concern).

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