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Melody
Dec 31st 2006, 06:20 AM
Crayfish - Paint Your Aquarium Blue With them
By Anthony Pang (http://EzineArticles.com/?expert=Anthony_Pang)


Crayfish originate from Australia and they are freshwater invertebrates. Most people call them 'blue lobster' and 'yabby'

There are many species within the Crayfish community. These beautiful creatures are hardy and can live to up to five years. Crayfish is much sought after as aquarium pets due to their fancy varieties and brilliant color.

How do you select healthy crayfish?

You have to avoid shops where they kept all the crayfish in overcrowded tanks with very little water. These crayfish tends to become stress and eventually die in such condition. Look for crayfish that is lively and full of energy. You have to also make sure that they have a complete set of limbs. You can test it by lowering your hands onto its back. When a healthy crayfish sense your hand, their natural reaction is to move back and raise both their pincers in a defensive stance. If the crayfish simply lie still and does not respond to your touch, you can be sure that it is not healthy.

Their pincers are used to catch prey and protect themselves. Sometimes you may notice that some of the crayfish have pincers that are smaller than most of the other crayfish in the tank, or they may have pincers that are not of equal size. This can be that the smaller pincer is a new appendage that grew while replacing the old one.

It is a little tricky to catch crayfish. You have to approach it from the back and hold the end of its carapace with both your thumb and index finger

Crayfish is unlike some of the fishes. They are territorial in nature, and so you must never over-stock your tank. So how big should a tank be? Well, 2ft by 1ft will be big enough to keep the crayfish happy.

Crayfish likes hiding space. You can place objects in the tanks. Objects such as PVC pipes or rocks will be able to provide them lot of good hiding places.

For aeration, a bubble filter will do just fine. And take note that crayfish do not need strong lightning and they do not do well in acidic water.

When it comes to feeding, it is the easiest! Crayfish eat anything they can find. It can be dirt, unwanted scraps, and feeder fish, sinking pellet or just some shrimps. Anything, everything goes for these creatures. Crayfish hunt at night, so turn off the aquarium light before you feed them.

Crayfish tend to grow by getting rid of its old shell. They will push itself out of the old shell through the space just behind the carapace which will split open. When they shed their shells, they will be covered only with soft tissue. These soft tissues will harden into new shells after a couple of days.. And usually, the crayfish will eat up its old shell.


For more resources on home fish and aquarium experiences, please visit Aquarium (http://www.anhwohe.info/aquarium/index.php).
Article Source: http://EzineArticles.com/?expert=Anthony_Pang

Melody
Dec 31st 2006, 06:24 AM
Breeding Crayfish
By William Berg (http://EzineArticles.com/?expert=William_Berg)
AquaticCommunity.com (http://www.aquaticcommunity.com)


In the text below I shall try to give a short overview of some of the basics when breeding crayfish. Particular species may have other behaviours and demands. It should be said that my main experience as an aquarist is with relation to fish, but I shall try to convey what little knowledge I have.

Sexing Crayfish

Sexing crayfish isn't always easy. The genital openings are located in different places on the body depending on whether it's a male or a female. Males have their genital openings behind/under their posterior pair of legs. Females have their genital openings under the third pair of legs counted from the posterior. However, many individuals have a male as well as a female genital opening, making the sexing much more complicated. But these are always either male or female; usually male but you can't be sure.

Mating and egg carrying

In aquariums, spawning is possible any time of year. The male makes a little sperm packet and places it on the female's stomach. The female then spawns her eggs, passing them through the sperm packet so that the eggs get fertilized. It is not uncommon for the female to lose a claw during this process. She then places the eggs under her tail where they will be kept until they are ready to be released. How long this will be depends on the water temperature and the species, but it will be at least 4 weeks. A lot of other factors can also affect the length of the egg carrying period, such as water quality, and food supply and quality. The mother will watch over the young for a short time after birth.

Fry

The fry are very small when they are born but are fully developed miniature crayfish. Fry are usually detritus feeders, which means that they will feed on any decomposing plant parts and food leftovers they can find while scouring the bottom. Vegetable food is preferred and they can be fed boiled lettuce leaves that are left to decay in the aquarium. Be aware of the water quality. Fry are often very cannibalistic and a large aquarium is required if you want a higher number of fry to survive. Sorting fry for size may help the survival rate.

Breeding

Now you know about their breeding behaviour and how to raise the fry, but how can you get them to breed in the first place? Well, first of all you have to give them the right environment and good food to get them in a condition in which they can spawn. Some species also need different triggers to breed. These triggers may be a change in the amount of light and number of light hours, a change in temperature, change of circulation, etc.

Feeding

Crayfish usually accept most kinds of food, and I would recommend feeding them a diet based on boiled lettuce, sinking pellets, shrimps, and once or week or so, fish meat. This will get them in good condition and help the female survive the spawning period since she usually doesn't eat while she is carrying eggs.

Housing/environment

Many crayfish species can be kept in relatively small aquariums, but I recommend using larger aquariums since this lowers the pressure on the females by the males. The aquarium should be decorated so that a lot of hiding places of suitable size are provided. Hiding places can be created using rocks, roots, flowerpots, coconuts, PVC pipes, and so on. It's important that there is at least one, and preferably several hiding places for each crayfish.


By William Berg of Sweden, for http://www.aquaticcommunity.com
About The Author
Article by William Berg originally published at http://www.aquaticcommunity.com. Article may be reproduce as long as it is not edited and a live link to http://www.aquaticcommunity.com is placed in the article header. (java links and PHP links are not allowed) Included this resource box “as is with live links” on the bottom of the page.
Article Source: http://EzineArticles.com/?expert=William_Berg

Canadiancray
Mar 23rd 2008, 12:25 PM
Crayfish - Paint Your Aquarium Blue With them
By Anthony Pang (http://EzineArticles.com/?expert=Anthony_Pang)


Crayfish originate from Australia and they are freshwater invertebrates. Most people call them 'blue lobster' and 'yabby'


Might want to clarify that statement. Crayfish don't originate from Australia LOL.

Melody
Mar 23rd 2008, 12:43 PM
Tell it to the writer or expand on it here - I didn't write it.:smile:

grumpystiltskin
Mar 23rd 2008, 12:57 PM
There are crayfish in every little puddle of water in Australia, as far as they originate from aus, i dont know either !! but as a kid i used to catch them all the time, we put a piece of meat in a nylon( stocking) and attach a piece of string, and leave it there for a while ,then slowly lift it out and bingo a yabby is trying to eat the meat,
We would eat some of them, and use some of them for bait. i never thought to use one in a fish tank.

Melody
Mar 23rd 2008, 01:11 PM
He mentions blue crayfish, and three of the four blues that I'm aware of come from Australia. Chances are he was being specific and then launched into a general info article. If anyone would like to actually expand on that information, that's great!

So I take it walking barefoot in mudpuddles is not a good idea in Australia Mick? lol

Canadiancray
Mar 23rd 2008, 01:21 PM
Basic Guidelines for Crayfish Care

All species of crayfish require clean, well oxygenated water. The water must be circulated with a good filter or air stone of some kind at all times. Crayfish will drown in stationary water in 6 hours due to the fact that oxygen will settle to the top of the water column out of their reach. Water parameters should be Ammonia 0, Nitrites 0, Nitrates <=10

North American crayfish due best in waters between 60F & 75F with 72F being optimal. Australian crayfish are generally the same with the exception of Cherax Quadricarinatus (Australian Red claw). They can handle tropical temperatures as they are from the tropical region of Australia near Queensland. Keeping any crayfish in water warmer than they are used to in nature can cause your crayfish stress, make them grow faster which in turn will cause a shorter lifespan.

All crayfish have basically the same requirements when it comes to food. They are all scavengers in nature & will eat whatever you give them or whatever they find in the tank. This includes plants & whatever fish they can catch. The general rule is a good quality shrimp pellet or one of the many specialty foods avail. Like Hikkari Crab Cuisine or HBH Crab & Lobster BITES. They also enjoy the odd frozen pea, potato & carrot. If you do it correctly the can also be trained to hand feed taking the food right from your fingers. They should be fed once per day max or every other day. Remember in nature they aren’t going to find food everyday. Once they reach approx. 6” in size this amount can be increased.

All species of crayfish are great at escaping. Trust me it’s happened to me many times when I thought it wasn’t possible. They love to climb & will find any small opening in your lid. Secure all openings around filter intakes, airlines etc. I mean secure like with duct tape. Or sheet metal & a welder. LOL just kidding. If they do get out they can survive for a few hours but only as long as their gills remain wet.

It is generally considered a bad idea to keep more than one crayfish in the same tank together as they will fight & possibly kill each other. Although this is a personal decision you will have to make as many people keep multiple crays together. If you do decide to keep multiple crayfish together make sure they have many, many hiding spots. They will need them when they molt to stay safe from predators. North American crays require at least 10 gallons per crayfish & Australians require from 30-50gals per Crayfish depending on species as the Aussies can get VERY large.


By Craig Williams

alLexX
Aug 15th 2011, 09:24 PM
i have a large blue cray(female),who i beleive is procambarus alleni. i can vouch for them being good at escaping,once she climbed out of her tank and into another,and slaughtered my african dwarf frogs(R.I.P.). another time,she got outta her tank and walked like 30 feet to my kitchen. after dropping 12 inches out of her tank to my desk(the stand) and 3 feet to my floor. yes,i made a cover but took it off for the second time because i wanted to see her get out. she also takes food from my hand

CACAdmin
Aug 15th 2011, 10:46 PM
What a little mischief maker your blue cray is!