My New Green Wolf Eel

[Dave Legacy]

Say hello to my new Green Wolf Eel (Congrogadus Subducens). He's not actually a true eel, but a pseudochromis/dottyback. GWEs are always sold as Marine fish, but after doing some research online I found fishbase.org saying that these guys are often times found in coastal brackish areas. I decided to give it a shot in my GSP tank but waited until my salinity was up in the 1.016SG area before trying out the GWE.

The other issue was the potential fighting that might go down. This GWE is a male, 7" in length, about .5" in diameter, and a lime green that often shifts into a shade of lemon. He's too small to eat the 3" GSP but I'll still continue to monitor them as he grows. This morning my wife noticed that the GWE had a nip on it's tail but that will heal, a litle bit of experimenting is bound to take place.

1.016SG is practically considered marine so I can't say for sure how low of a salinity this Green Wolf Eel would tolerate; I wouldn't exactly call it a brackish fish. Here's the pics:

We let our 4mo old son, Evan, name the GWE. The only thing he says is "Ahgoo", good enough for me.

- David

 

[AMS]

Tank looks great Dave! Any full tank shots? I can not speak from first hand experience with Congrogadus Subducens, but it could possibly grow at a faster rate than the GSP and potentially eat him. This would be a death sentence for the puffer as well as the eel due to the tetraodotoxin the puffer contains.

 

[SLC Flyfishing]

Not to defend the feeding of a puffer to an eel, but GSP's aren't toxic. If the eel were to ever eat the puffer, (which I doubt would ever happen) he would be just fine.

 

[AMS]

If I remember correctly, they do have a small level of poision though not at all large enough to effect a human but probably a fish such as GWE. I could be wrong though

 

[SLC Flyfishing]

Ok that could be true, but I doubt it. As a pre-medical student, I have been tracking a new medication (anesthetic/analgesic) that is made from refined tetrodotoxin. The GSP is not mentioned as one of the species that can be used to get the toxin. They only need a few micrograms for the medication so I seriously doubt that they are toxic. However, I don't think that the eel could eat the puffer because of the puffing action. I'm rambling, i'll shut up now. Good luck with the tank.

By the way the med is called Tectin. It appears to be more effective than morphine and as of yet, side effect free. You should check it out, it's fascinating. To my knowlege, the only puffer that is common among freshwater aquarists that is toxic is the Green Puffer, which grows much larger than the GSP and is very aggressive. It may be a good consideraton for tankmates with a large eel.

 

[nmonks]

The subject of the toxins in pufferfish is interesting, and complex.

Freshwater puffers don't have the same toxin as marine ones, for a start, they have something called "saxitoxin". The freshwater species have it in the skin, while marine species have the toxin in their internal organs. Some species don't have the toxin at all and are quite eaten as food without special preparation (not sure which ones though).

In captivity all puffers lose the toxin. Puffers cannot synthesise the toxin from scratch. The puffers need to ingest certain bacteria, and only then can they make (take from the bacteria?) the toxin.

The reason why the toxin is used in medicine is because, I think, it acts only on the nerves and doesn't do any other damage. If someone is poisoned by tetadotoxin, their nerves shut down, and they die from suffocation or cardiac arrest. However, if you keep the patient alive on life support, the toxin eventually fades away, and the nerves work again, none the worse for wear. Presumably no addictive properties (except maybe a desire for dangerous sushi!).

All this stuff is explained in some depth in the Aqualog pufferfish book.

Cheers,

Neale

Ok that could be true, but I doubt it. As a pre-medical student, I have been tracking a new medication (anesthetic/analgesic) that is made from refined tetrodotoxin.

By the way the med is called Tectin. It appears to be more effective than morphine and as of yet, side effect free. You should check it out, it's fascinating.

 

[Dave Legacy]

AMS,

Here's the latest full tank shot. It looks super ugly right now but I just don't have time to clean it up until the next PWC this weekend. Besides, now I have 2 biters to watch out for. Today I was feeding the GWE and while I was distracted by him the GSP snuck up and bit me. Haha! Oh, and the salt creep is ugly but it keeps my salinity at a steady level so I don't argue with it.

Here's the pic:

It's a neat pic because you can see both the GSP and th GWE. The tank is actually much taller than the picture let's on... I accidentally cropped the top off.

Here's "Ahgoo" in one of his usual hiding spots, amongst the weeds, where he adjusts his coloration to blend in better. It's often times very hard to spot him when he's in there.

So today I chickened out and raised the SG to 1.017 making it an acceptable marine tank. I'm really not sure if this is acceptable for my 3" GSP. Does anyone know? I was thinking I might slowly lower .001SG each week to help the GWE adjust unless the salinity is ok for the GSP. In which case I'll just leave it how it is.

- Dave

 

[SLC Flyfishing]

My GSP is in 1.018 and has been for a few months, he has seemed much more happy and active than he was in a lower salinity, he was quite good before though. My GSP is only about 2.5 - 3 inches in length.


in response to the post by nmonks, yes the toxin works on the sodium channels in the nervous system. the tetrodotoxin molecule has an end which fits nicely into the sodium receptor. the problem is that it stays there for tens of seconds, whereas the sodium ion only stays for a few nanoseconds. This basically creates a traffic jam in the nervous system as you can imagine, none of the organs can get their signals. that's why the medical form is given in such a small dose, in very small amounts, the first nerve signals to be shut down are the pain signals. The toxin to my knowlege is not used commonly in medicine yet, it is still in clinical trials in canada and china and doctors in the united states weem to be fairly closed to the idea, the only reason I have been able to find is that to them morphine works very well so why try anything else?

As far as saxitoxin, I thought that only shellfish possed that, I'll have to do some more research. Anyway, the tetrodotoxin is synthesized by bacteria, that is correct, sort of a symbiotic relationship, the puffer provides a home for the bacteria, the bacteria provide protection. I'm not telling you anything you don't know but I like to discuss it, it's fascinating. It's the only reason I got into keeping puffers, I want to become an anesthesiologist as my profession. The puffers are inspiration for me because of their potential medicinal properties.

anyone who would like a well articulated explanation of the human physiological implications of ttx could visit the wex technologies website.

sorry about rambling on about something that's not really relevant to the posted question, guess you could talk about it in the tff pet peeves thread over in tropical chit chat. wex technologies