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Chucky228
06/02/2010, 03:27 AM
Lighting
I've seen several posts about recommended lighting for a mantis the past few weeks recommending florescent bulbs (actinic) under like 50 watts. When I first got my mantis (about 1.5 yrs ago) he was just a little 3'' baby. I used a 150k metal halide over him for about a year before I switched to a compact florescent fixture that I bought off of a friend with two 65 watt bulbs (1 actinic, 1 10k). I'm looking into getting a single or double florescent fixture with 2 x 17 or 25 watt 50/50 actinic blue and 6k bulbs because I think the 2x65watt bulbs are too powerful. He has always had a pitch black den to hide from the light but he rarely comes out (peacock mantis in a 40 breeder btw). I can just see his eyes peering out every time I walk into the room. Do you guys think that the 65 watt bulbs are causing him to not want to come out? Are the 2x65 watt bulbs too bright for him to be comfortable? What amount of light do you guys use over your tanks? I just wanted to check with some happy mantis owners before I make my new lighting purchase :lmao:

Shell Disease
Another concern is that the metal halide and possibly the 2 65 watt bulbs started some shell disease. I first noticed pronounced black/ brown spot on his back that looked as though someone burnt the edge of his shell a few months back. I fed him earlier today and it looks worse. I turned off the 10k bulb so that I'm just running a single 65 watt actinic till I get it checked out. I don't actually know if its shell disease. I just want to be safe with the lighting. Do we know how long it might take for a mantis to develop signs of the shell disease? The spot looks nothing like the photos from the shell disease post a few days ago. I didn't want to hijack the thread because mine is mostly about lighting. Just curious. I’m not too worried about it until I can get a better look at it. I might take some pictures or a video.

DanInSD
06/02/2010, 10:22 AM
What species? What size? What age? How big of a tank? What shelter (rock? white pvc? gray pvc?) ? What water parameters?

Sounds like shell disease from your description but of course pictures would be helpful.

Dan

Chucky228
06/02/2010, 04:24 PM
http://www.youtube.com/watch?v=ah-Dxa7sTUg

I tried to get a good angle for the video. I'm not sure if you can see it that well. Its a Scyllarus, about 4-4.5 inches long, I've had him for a year and a half but i'm not sure how old, 40 gallon breeder, and a pure live rock shelter. The parameters are good.

JokerGirl
06/02/2010, 07:55 PM
Looks like shell disease to me. You might want to increase feedings to try and force a molt and pull the shed out before he can eat it. I'm sure Roy will chime in with more info. Get rid of the halide.

Chucky228
06/02/2010, 08:15 PM
I was scared to hear that answer. I knew the metal halide was too much for him but I didn't have much of an option at the time. How much light do you guys have over your tanks?

Thurge
06/03/2010, 09:16 AM
I know several people don't light their Peacock tanks. They just let the ambiant light from the room its in light the tank.
If you have one or can get one from a friend, Dr. Roy has recommended using a UV steralizer in the past. While the exact cause or causes are unknown Dr. Roy has indicated that their may be a water born vector that contributes to shell rot.

To add to Jokergirl up your feedings and soak your frozen foods in a good vitimine suppliment like Selcon.


Take heart I beat Shell Rot in my G.chiragra. He had shell Rot and hair algae growing on him when I got him, and I had him for at least 4 years.

Chucky228
06/03/2010, 04:50 PM
wow. That's amazing. I'm glad you and your G.chiragra were able to beat it. I have a bottle of Selcon that I'll start using with the frozen food. I was using it every once and awhile when I remembered.

Unfortunately, I don't know anyone who has a UV sterilizer but i will defiantly do some looking around.

Ambient light for the tank huh. My only problem is that the tank is in a room that never gets any sunlight (blocked by hedges and trees) and the windows act like sunglasses. Its pretty dark 24/7.

Chucky228
08/21/2010, 06:15 PM
He molted!!! :bounce1: I noticed the white stripe on his back a few days back. I took a peek inside this afternoon and he was on his back but still moving. I don't remember what those fin things are called under his body. Anyway, I checked 30 min later and he had molted. I was lucky enough to be able to remove the molt. He has not come out yet but I'm hoping that his shell disease will be gone. :worried2:
I switched to a single actinic florescent 20watt bulb and he did become more active. I would catch him roaming the tank from time to time. I fed him every other day and used Selcon frequently. I hope it all worked. I'll check back when he feels comfortable enough to come out and feed so I can see if the rot is gone :)

stepho
08/21/2010, 11:48 PM
Shell Disease in O. scyllarus Revisited (Dr. R. Caldwell)

I recently received another request for information about shell disease in Odontodactylus scyllarus (Peacock Mantis Shrimp) and I though it might be useful to post my response. For those of you who have seen this before - sorry!

Erosion of the cuticle is commonly called "shell disease" in crustaceans. There are probably many different causes. This really just describes the symptom which includes discoloration and eventual erosion of patches of exoskeletion. Why shell disease is common in O. scyllarus is unknown, but large males in particular seem particularly susceptible. It is not just a disease of the aquarium. I have seen many animals in the field with it. Another large burrowing species, Hemisquilla californiensis, also seem particularly susceptible. I have also seen it in large Gonodactylus chiragra. My impression is that larger smashers that don't molt very often are most likely to get it.

We don't know the cause or even the primary pathogen. Usually by the time you start to notice rusty brown discoloration of the cuticle - typically on the carapace or dorsal abdomen, erosion has started and there is a whole community of fungus, bacteria, protozoa, etc. feasting on the diseased tissue. Gradually the patches spread and deepen until they eat entirely through the exoskeleton. At this point the disease is usually fatal. It weakens the animal and/or makes it impossible for it to molt successfully.

I know of no "cure", but there are ways to treat the disease. It makes sense that antibiotic dips might help, but I don't have any information on this. Unfortunately, stomatopods are quite susceptible to chemicals like formalin and other treatments that are used for skin diseases in fish, so I would not recommend experimenting. The good news is that if the disease does not advance too far and the animal successfully molts, they can literally shed the disease and recover. This is one case where I would recommend immediately removing the molt skin and not allowing the animal to bury or eat it.

I have found a few things that help. First, water quality seems to be key. Be sure your nitrites and nitrates are low. Also, good circulation seems to help. O. scyllarus do well in fairly strong currents. (I've collected them in areas where the currents were ripping at 2 or 3 knots.) I have also found that uv sterilization of the water seems to slow the disease and also reduce transmission to other stomatopods. (Actually, I haven't done the experiments to prove that it is contagious. It is difficult to separate out various environmental conditions that might cause the disease from transmission from another animal.) Strong lighting also seems to cause problems. A deep, dark burrow (black or grey pvc pipe at least twice the length of the animal and just a little bigger in diameter is about right) also can help. A good diet is also important. If I have an animal that shows signs of shell disease, I usually start adding supplements such as "Selco" to its diet. This is one time that I recommend feeding the animal as much as it will eat. The more quickly it molts, the better the chance that it will get rid of the diseased tissue and recover. Just be careful to remove uneaten or buried food to maintain good water quality.

I wish I could offer more help, but in general I have found that if I catch the disease early, take care of water parameters, hook up a uv filter, reduce lighting, increase flow, and add supplements to the diet, the animals usually survive. Sorry if this sounds like the usual laundry list of aquarium care, but it seems to work.

- Dr. Roy Caldwell

Found that here: http://www.blueboard.com/mantis/care/shell_disease.htm