Marble Crayfish Help PLEASE?!?!?!

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Mavrick813

Candiru
MFK Member
Dec 28, 2010
980
4
48
Hamilton, NJ
Purchased 4 1/2"-1" Marbled crayfish the other day. Set-up a 20G L with pea gravel, a whisper 10/20, and 2 sponge filters that I seeded in my Os tank, The water for the Crayfish tank also came from my O tank.

I've been putting crushed up sinking shrimp pellets in their for them as well as some sinking Cichlid pellets. Found a dead cray today. Only thing I can think of is the water temp. Tamp is sitting at about 70*, I asked in another thread if the Marbles need a specific temp or if 70* is ok but got no response.

Any ideas? Also, should I take the dead one out or leave it for the other 3?

Mike
 
What are your water parameters? ammonia/nitrite/nitrate/ph
I keep mine at 68 degrees, that would not kill him though. Take the dead one out.

How often do you clean the tank. They can be aggressive so one may have killed another but they tend to be more of the mellow species. They make lobster food at big als. Mine love it.
 
is it a dead crayfish or an empty shell from one of them moulting? back when i kept crayfish i kept them in the tanks with my cichla and other south american cichlids. and the temps were always (almost) over 80 degrees..
 
Put the Heater in and adjusted the temp to 72. Got one cray alive and kicking, Eating Peas.

Second cray has lost his claws and is struggling. He's not leaving the pipe he's in and is mostly on his side. I know he's alive because his tail flicks and his legs go crazy every so often. I squished a pea and put that right by him using a pair of tweezers.

Third and Fourth crays both bit the bullet and have been removed from the tank.

0/ 0/ 0/ on the water. Will Check PH in a bit. I took 50% of their tank water form my Oscars tank, 50% from tap, Added Prime and 2 Seeded Sponge Filters from my Oscars tank. I let it run for 1 week before adding the Crays.

I think that the problem was that they weren't eating what I was giving them. I had sinking Shrimp Pellets, Flake, and Sinking Cichlid Pellets. Either they weren't eating it and starved or I over fed. Never had Crays before but the one guy is doing just fine. Pretty cool watching him dart out of his PVC pipe and go after a Pea that I squished between my fingers then dart back in. If I turn the lights in the room off and use my phone to watch him He comes out climbs to the top of the one sponge and floats back to the bottom. He'll do this for hours it seems. So I've left the lights in the room off.
 
Are you positive you have Marmorkrebs? There are quite a few species that get labeled and sold as "Marmorkrebs" and "Marble/d Crayfish" when they aren't, in which case the temperature, food, pH levels, etc may have been completely wrong for them. Because krebs are very hardy and tolerate of most set-ups, temperatures, foods, etc... it's why there's invasive issues with them in Europe, the states and Madagascar.

But that aside, I'd check on the pH... if there's something off in the pH it could be inhibiting their ability to get oxygen and burning out their gills. Other than that, crayfish that small are generally susceptible to a variety of issues and they die off easily. Once they're larger, they're a lot hardier.
 
well, take the dead one out for sure, and i have a crayfish i caught from the river and he eats monnows, im sure your will eat the same thing, ive never seen any crayfish eat pellets, but they might eat shrimp. but i think they prefer live foods
 
PH should be high, but what really matters with crays is hardness. Lots of cuttlebone, crushed coral, natural gravel, etc. Get that water hard and get a real test kit that doesn't give you straight zeros. Something is probably wrong if you have 0 nitrates.

70º is fine. Scientists found that 68º is the absolute perfect temperature for marmorkrebs, but a couple of degrees either way will not change the survival rate enough to matter.

Where did you buy them from? How much different was their water from yours?
 
Mine love sinking cichlids pellets. You can change their color by what you feed them. I've had them blue, red, brown and green. Kensfish makes an invert food with veggies and calcuim. Mine love it. Like blacksun said they are hardy. I didn't clean the tank or filter in 2 years, just dripped fresh water and once they got going they went crazy. I also didn't use a heater but the room they are in keep the temp in the mid 70's.
 
black_sun;4882786; said:
Are you positive you have Marmorkrebs? There are quite a few species that get labeled and sold as "Marmorkrebs" and "Marble/d Crayfish" when they aren't, in which case the temperature, food, pH levels, etc may have been completely wrong for them. Because krebs are very hardy and tolerate of most set-ups, temperatures, foods, etc... it's why there's invasive issues with them in Europe, the states and Madagascar.

But that aside, I'd check on the pH... if there's something off in the pH it could be inhibiting their ability to get oxygen and burning out their gills. Other than that, crayfish that small are generally susceptible to a variety of issues and they die off easily. Once they're larger, they're a lot hardier.

Positive their Krebs, Got them from a member on MFk. The one that was doing well has molted twice already and I have also bought the mother from the same MFK Member here. The adult and the one baby are doing fine now. Eating well and thriving. As for PH it's in the 7.2 - 7.4 range.


matt campbell;4911423; said:
well, take the dead one out for sure, and i have a crayfish i caught from the river and he eats monnows, im sure your will eat the same thing, ive never seen any crayfish eat pellets, but they might eat shrimp. but i think they prefer live foods

Dead ones were taken out. From the reading i've been doing Marmorkrebs don't really go after fish. I haven't tried, but it's what I've read. However my one baby that lived, and the mother I picked up both readily snatch the Algae Wafers and Sinking Shrimp Pellets. They also devour fresh Kale.

knifegill;4911435; said:
PH should be high, but what really matters with crays is hardness. Lots of cuttlebone, crushed coral, natural gravel, etc. Get that water hard and get a real test kit that doesn't give you straight zeros. Something is probably wrong if you have 0 nitrates.

70º is fine. Scientists found that 68º is the absolute perfect temperature for marmorkrebs, but a couple of degrees either way will not change the survival rate enough to matter.

Where did you buy them from? How much different was their water from yours?

I should get myself a Cuttlebone and add that to the tank. I haven't thought of that, thanks for the tip. I have an API FW Test kit that I use for my Oscars. It's only a month old and reads dead on. At the time of the OP They had only been in the tank for about a week. And the levels were 0 /0 /0, ATM the levels are 0 /0 /10. Also, I got them from hernandez.j91 here on MFK http://www.monsterfishkeepers.com/forums/showthread.php?t=389630 Great Seller, Fast ship, Very helpful. As for water comparisons, We didn't do that so I don't know.



Danger_Chicken;4946850; said:
Mine love sinking cichlids pellets. You can change their color by what you feed them. I've had them blue, red, brown and green. Kensfish makes an invert food with veggies and calcuim. Mine love it. Like blacksun said they are hardy. I didn't clean the tank or filter in 2 years, just dripped fresh water and once they got going they went crazy. I also didn't use a heater but the room they are in keep the temp in the mid 70's.

Thanks for the tip on the Kensfish food. Didn't know about it. Going to get that to add into feeding rotation. I haven't gotten any babies yet but the adult Kreb I picked up was brown when I got her and is now Blue. She is eating mainly, Kale, Algae Wafers, and Sinking Shrimp Pellets.

Mike
 
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