Electric Blue Crayfish Questions

[Daryth Darkmoon]

Hi. I have had an electric blue crayfish (or lobster as some are inclined to call them) since February. She did well in my community 10 gallon but was growing large fairly quickly. So I set up my 50 gallon and moved her and every other fish I owned over into the larger tank. They did well for a few weeks, and then fish just started disappearing.

Warning to anyone interested in crayfish, THEY WILL EAT YOUR OTHER FISH!

Too bad I lost my koi angelfish before I ever found out there was a problem. Of course I bought it at Wal-Mart and went by the info card they had posted without doing my own research. The info card said they were non-aggressive and good in community tanks.

Thats just background history though. The question I'm wondering is how often will they molt? One site I was on said they would get up to 6 to 8 inches in length, and mine is up to about 4 inches now. She was only about an inch and a half when I bought her.

She is currently in quarantine until I put a divider in my 50 gallon so she'll stop eating my fantails. I'll probably toss in the occasional feeder gold for her, since she seems to prefer the live food.

I know the problem with her eating the fish isn't due to lack of food. She'll ignore the food and go straight for the fish!

But I digress. Again my question was about growth. Though any and all advice from someone experienced in dealing with crayfish would be most appreciated.

Oh and here is a pic......

 

[lovemybarbs]

Yeah, mine lasted a day and went back. He tried to eat my ADF.

 

[Daryth Darkmoon]

Yeah, mine lasted a day and went back. He tried to eat my ADF.

True enough, but I like my crayfish and I don't think Wal-Mart is in the habit of taking fish back. Though I had briefly considered calling the local fish store when he ate my koi angelfish. Going to take me some time to replace that one since I don't shop for fish online.

 

[tropicfishman]

walmkart is notorious for posting that all the fish are peaceful lol the crayfish will catch anything that sleeps or moves slow enough and its not a pretty sight

 

[Daryth Darkmoon]

walmkart is notorious for posting that all the fish are peaceful lol the crayfish will catch anything that sleeps or moves slow enough and its not a pretty sight

Yeah, he got my pleco the other night when some friends were over and they (Laser) felt the need to give me a play by play. I have some nice high res photos and my other friend has video of the incident. He does so love his digital camera. At least I got some nice shots fo the crayfish out of it.

 

[Lonewolfblue]

As for molting, they will molt several times a year, more when they are younger, and as they get older, it will slow down.

 

[Menagerie]

I'll probably toss in the occasional feeder gold for her, since she seems to prefer the live food.

That's not necessary, since feeders may introduce disease into your tank. The crayfish is opportunistic and simply eating what's around. My crayfish loved all sorts of food--pellets, wafers, flakes, frozen food, algae scraped off the side of the tank....(pics in my gallery)
They certainly do molt often when they are young--4-5 times a year.

Warning to anyone interested in crayfish, THEY WILL EAT YOUR OTHER FISH!

Yes they will. I am going to use this topic to reinforce that to others who ask, "What fish can live with my crayfish?" Sorry you had to learn that lesson the hard way. Crayfish are best in a species only tank with no tank mates, not even another crayfish. Also be aware that they are escape artists--mine was in the habit of walking across the living room and one day I found him too late under the fridge He would climb the heater cord and no matter what we did, he would get out. Speaking of heaters, crayfish are not tropical and prefer 68-70*F, which is another reason not to keep them in with tropical fish.

 

[Daryth Darkmoon]

be aware that they are escape artists

Yeah, I had mine in the kitchen for a short time in my 10 gallon while the 50 was cycling. I found her under the fridge, thankfully both in time and not squished when I pulled it out to look for her.

crayfish are not tropical and prefer 68-70*F, which is another reason not to keep them in with tropical fish.

The interesting thing about that is that even without the heater my tank stays around 78*F. My crayfish doesn't seem to really be affected by the warmer temp.

The heater is going to be on the opposite side of the tank when I put in the divider, to help maintain that temperature in the winter for the angels I want to add.

 

[QTOFFER]

The nice thing about crayfish is that one requires a relatively small tank (at least 5 gal) and no heater. They prefer and will live longer in cooler water. They need alot of oxygen, so make sure your water is being agitated - my cray loved to sit on the airstone. They are expert escape artists, as Menagerie mentioned.

You don't need to feed live food, although they will certainly eat it. I used to give my cray all kinds of sinking pellets, thawed veggies, and an occasional small piece of tuna or cooked chicken. They make a huge mess when eating and like to hide stashes of food for later - in other words, gravel vac often! Don't ever feed live or raw shrimp because there are diseases that crays can catch from their FW and marine cousins.

 

[Daryth Darkmoon]

Thanks all for the advice so far. It has been both helpful and appreciated.


I am concerned though about tank size.
I was going to put her in my 50, since I was told they can grow up to 6 - 8 inches in length. Would a 10 gallon be large enough for her, even at that size?
Oh, and I was wondering how crayfish do with live plants.

 

[DeFeKt]

not all crays prefer cold water, but even the coldwater ones thrive and breed in warmer temperatures.
Seeing as there are hundreds, even thousands, of different types figuring out which one you have will be near impossible.
I would keep it in a 'middle/happy medium' type of temperature.
They eat vegetation and will rip it up just for the fun of it, so if you want to be constantly replanting and restocking plants, it's up to weither you will want to do this or not.

They can molt anywhere from monthly to yearly, and as was said the younger ones will molt more often, leave the shell in there for them to eat, if it has no interest in it, remove it. Makes a great mantle decoration if you can get it whole!!

btw, even the smallest of angels will be uncomfortable in a 5 gallon section of a 10, so try to get something bigger for them and let the cray roam the 10.

Also be aware that they are escape artists--mine was in the habit of walking across the living room and one day I found him too late under the fridge

I to have had that elusive cray, he managed to walk through the living area, down the hallway past all the bedrooms and was found at the other end of the house in the 2nd bathroom, unfortunatly all dried up 2 weeks later.
They can survive out of water for a long time though, if outdoors most will just bury themselves to get the moisture out of the soil.

hth

Matt