In your experience how fast will a crayfish grow

good evening all,

I bought a crayfish 2 weeks ago. he was 3/4"(no claws) when I got him. He has molted twice in the 2 weeks. It wasn't until I got a second crayfish yesterday that I really noticed how big it had gotten.

the second one I got was the same size as the first when I got him. the first one has over doubled in size in 2 weeks.

After some research I have learned that the molt more often when they are young, but I haven't gotten any actual numbers on what is a usual amount.

he gets a lot to eat and I supplement the water with egg shells already for the snails and ghost shrimp, so his molts only take 4-6 hours.

i'm not worried or anything, he is obviosly a healthy growing critter, but I just wanted to get some feedback on other experiences with growth rates.

 

My blue cray was half an inch when I got her and has grown to more than 4 inches over the last year. They'll molt maybe once a month.

Multiple crayfish in the same tank is a very risky setup....they don't need/want friends.

 

yea, they are still small and have plenty of hiding places. I will have a much larger tank by the end of the year as well. its funny, for the last 2 days they have been cooperating with each other to try and hoard all the food that sinks.

 

I had a cray for about 3 months. moulted 5 times and when I retuned him to the LFS he was double the size of the others in their tank! All depends on how much food they can get, more they eat, faster they will grow

 

and the temperature of the water - warm water will cause them to grow faster

 

+1 to jaysee... their metabolism increases... a bit like plants with high light, so we give them fertiliser!

good luck with them!

 

They also grow each time they molt.

 

they grow depending on how much they are fed, a well fed cray will grow super fast

I have also found that water temp doesn't really affect growth, it does affect the metablolisim(sp?) . but my crays stay in cool waters and they grow like weeds.

(btw for those who don't know me from other forums, I have many many crays)

 

I'm so sorry to interupt this post but I have a question for theemon. When they molt can I transfer them into another tank so the other crays don't eat the molting one?

They grow pretty fast, each molt they grow bigger. Also it depends on the food you feed, variety is the key. Lots of veggies as well. I have lobster food, you can find it at big als, they love it. Lots of water changes and a nice clean tank will make them grow faster. They molt once a month.

 

The big one has molted 3 times in 3 weeks and has quadrupled in size. He eats shrimp pellets, zuccini, worms, fish food, algae wafers. HI'm and the little one(although he has already molted once and grown .5" himself) still work together to horde the sinking shrimp pellets.

 

well...the big one molted AGAIN last night. He has gone from .5" to 4" in 4 weeks. He is quite the monster now.

 

Can you get a pic????? I want to see this monster.

 

chick, I already answered u in a different post, but for anyone reading this post.
yes you can transfer them with little to no stress on the cray, BUT be warned when they moult they are super soft and to watch it with the net.

also chick, I prefer veggies only. I have found that if a cray gets fed meat the cray wants more meat, ya know? it makes mine more aggressive, and I have fish with all my crays so I feed mine veggie related foods

matt, in all honostly it sounds like your over feeding him. I'm not saying that your in the wrong, but your cray will get huge

 

Mine get tons of veggies, lettuce, they LOVE raw potato, zucchini, cucumber, algae wafer, marine algae, pellets, crushes eggs shells. Lots of variety but lots of veggies as well.

 

I have a lot of little pest snails that I see him snacking on. I think this is where he is getting all the protein and calcium from. he just picks them up and crunches them whole, it is quite the brutal site.

 

I see mine cracking on snails too. They love them, even though there just babies I give them lots of snails.

 

Here is the deal with crayfish.

According to the research that I did on the net, they molt about every 4-6 weeks. After each molt, which is a very tedious and dangerous process for them, they increase their size by about 20%. Their new shell is very soft so they tend to be even more skidish.

From my own experience, They molted anywhere between 2-8 weeks. Probably due to a number of factors (food, environment, and temperture to name a few).

Highly territorial, so please just keep one in a tank and provide sufficient hiding places.

Plants are not recommended either unless its intended for a snack.

 

According to the research that I did on the net, they molt about every 4-6 weeks. After each molt, which is a ... size by about 20%. .

this is complete generalization. like saying boys are tuff. and girls wear dresses. each moult depends on the crayfish itself, and a zillion other factors. and the size incrase verys widely.

 

I agree. This is what I read, which is the reason why I also wrote from my own personal experience to be more specific.

 

rather than remove the crayfish that molted, remove the crayfish that did not moult. the soft and newly moulted cray is easily injured from handling or often by the other cray.

 

if your rough in any way id sugjest torval's idea. however those with a soft careful hand can net a freshly moulted cray with no problems. how I do it is use one hand to make my cray walk backward and with the other hand place a net directly behind it. 95% of the time the cray will just walk into the net. but in honosty remove the hard shelled cray.

 

So the big one has molted a few more times and is now just over 6" long. He molted yesterday again, but his body did not grow, just his claws. They are huge and his now a danger to his tankmates. He grabbed a full grown Molly yesterday and devoured him on the spot. This morning he grabbed a medium sized Cory and sucked him down too. Frankly I am aggrevated with my LFS. I don't consider this to be a dwarf crayfish like I was originally told. I hold no ill will to the cray, but he may need to be rehomed.

 

your typical lfs owner will tell you anything to sell you something, and usually have no idea what they are talking about anyway. if the crayfish is 6 inches long (measurements of cray should be given from tip of carapace to end of tail, do not count the claws), then he is definitely NOT a dwarf crayfish. the only 2 dwarf species I know of rarely exceed 1.5 inches. I am betting they sold you a cherax quadricarinatus if it is really 6 inches. few NA crayfish get that big, and the most common austalian crayfish is the cherax quad.

 

Good morning,

This thread is a bit old. Try to remember to check the dates of the original post before responding.

Thanks!

Ken

 

They are fast growers.