In a few words; First defrost ceph (if it is frost), second, inject formalin ( optional if it is not too large) and put it in a big glass full of formalin. 10-15 days before, whash it 3 time with fresh water and preserve definitive in a 70% etanol solution.
Easy, but i'm wrong in some point of my post? Please say it if you desagree with me, and oviously why?
All you need the formalin for is to fix it. I guess just throw it in a bucket of formalin, maybe 50% formalin solution (not 50% formaldehyde! This would probably be fatal to every organic substance within a 20 mile radius!), 50% seawater. I'm not so sure about this stage as the octopus I got was already fixed. All we did was pour off the formalin with running water, in a controlled environment, and put the octopus in a large enough container and filled it with tapwater. I just left it steeping for a bout 2-3 days, changing the water about once a day! Formalin has a distinct smell, so you know that all the excess is gone when the animal stops smelling of the stuff. Then I suppose once it's washed out, you can put it in an ethanol solution... although technically I guess you could put it in distilled water since all the tissue id fixed anyway, but don't hold me to that! I think that's pretty much what we did, probably broke a couple environmental health rules but hey, at leats we got the specimen!! Mind you, my brain is shutting down due to too much exposure to dissertation-writing, so I might just be havering a lot of rubbish! But I did have a lovely Eledone cirrhosa which I donated to the uni as a study aid.
Supoosedly you can "deactivate" formalin by adding powedered milk. Formalin binds to any organic molecule, so technically it should basically turn to a toxic cheese! Although addmittedly I don't know about this, can anyone verify??
Supposedly you can "deactivate" formalin by adding powdered milk. Formalin binds to any organic molecule, so technically it should basically turn to a toxic cheese! Although addmittedly I don't know about this, can anyone verify?? Graeme
I've not heard of this being done before - it sounds like a neat trick though! I might give it a try this year.
Re the formalin soln concentration, you should never need to go higher than 10% (50% would be overkill - it would probably fix the outer surfaces of the animal and prevent the formalin from getting into the tissues, secondarily causing excessive shrinking and wrinkling); a 5% solution should be more than adequate for your standard small-bodied beastie (to ~ 30cm total length), although you should always inject a little into the viscera first.
Yeah! let us know what happens!! I wanna know if you get toxic cheese!!
When you say 50% formalin solution do you mean a sloution made up from 50% formaldehyde or a solution made up of 50% formalin (already prepared)? I think the guy at the aquarium used 50%formalin 50% water. I originall though the label meant the the solution had 50% formaldehyde, I was scared to even open the bucket! Yes, bucket; I had to drive from St Andrews to Dundee (about 20 miles) with the bucket on the pasenger floor!! Ane the road isn't well known for being overly straight!
The 5% formalin solution is made from already-made formalin (not formaldehyde!). Some sources recommend a 2-3% solution as being plenty, so you really don't need much. Basically a good safety rule for preservation is, do whatever tells you (unless you don't want to, and then don't ).