Marbled cray questions

[Kaosu]

Marbled cray questions

So i have found some mottled crays for sale around my area...5$ each.

ok so i have some questions, i have been researching them ...



what is the minimum tank size for 1 (,not including babies they will be removed soon as they leave the mom, and be added to my 40 gallon to be picked off as found. )
what is there max size
do they eat plants
will they eat guppies/fry
water temps
substrate?


what i have is a 3 gallon bow front with a 10 gallon in tank filter( kinda big i know)
it would bet 50% water change every other day,

the ones i am looking at are a bout an inch long...how fast do they grow

I can set up my 10 gallon again in a few months...but im tight on space for now and wondering how long the 3 gallon would work.

Any info would be great, thanks!!


Another idea i could keep it in a critter box (clear about 3 gallon size slotted lid) in my 20 long guppy tank if it will eat them...just ideas i really want one but need to know if my set up will do for one.​

 

[black_sun]

First, "mottled" crayfish can be any number of species which can grow to a variety of sizes and require many varied types of set-ups. Most fall under generic sizes and requirements, but there's still the occasional oddball.

But for Marbled Crays (Marmorkrebs) specifically, here's some generic info I've compiled: http://thecrayfish.forumotion.net/t76-general-info

You can do single crays in very small tanks, I've kept my favorite adults in 2.5 and 5 gal before just fine. Larger is better though, since they are active and will readily explore and move about.

Temperature wise, they can tolerate a wide variety of temperatures. It's why they're invasive in Germany and Madagascar, and now in several places in the US. So don't worry about the temperature too much, if you want them to breed rapidly though, a lower temperature will work (mid 60s).

Everything else is really up to you... they will munch on plants and on rare occasions take live prey. But they aren't overly destructive to planted tanks, nor are they as aggressive and predatory as P. alleni or P. clarkii (Electric Blue and Red Swamp crayfish), so they do well in a variety of tank set-ups. You can try out a variety of things and see what works out best for them and best for you. I've kept some of mine in planted tanks, kept some in my live-barer tanks, kept them in buckets with air pumps, etc.

 

[Fat Homer]

i keep mine in a 10G with no problems... lots of driftwood and temps around 28 degrees Celsius.

As for plants, couldn't tell you if they are destructive against them as my apple snail ate them all within a few days time...

 

[Kaosu]

First, "mottled" crayfish can be any number of species which can grow to a variety of sizes and require many varied types of set-ups. Most fall under generic sizes and requirements, but there's still the occasional oddball.

But for Marbled Crays (Marmorkrebs) specifically, here's some generic info I've compiled: http://thecrayfish.forumotion.net/t76-general-info

You can do single crays in very small tanks, I've kept my favorite adults in 2.5 and 5 gal before just fine. Larger is better though, since they are active and will readily explore and move about.

Temperature wise, they can tolerate a wide variety of temperatures. It's why they're invasive in Germany and Madagascar, and now in several places in the US. So don't worry about the temperature too much, if you want them to breed rapidly though, a lower temperature will work (mid 60s).

Everything else is really up to you... they will munch on plants and on rare occasions take live prey. But they aren't overly destructive to planted tanks, nor are they as aggressive and predatory as P. alleni or P. clarkii (Electric Blue and Red Swamp crayfish), so they do well in a variety of tank set-ups. You can try out a variety of things and see what works out best for them and best for you. I've kept some of mine in planted tanks, kept some in my live-barer tanks, kept them in buckets with air pumps, etc.

yeah the self cloning ones are what im talking about,
what is there max size? and how fast can i expect them to get there from 1 inch.

^_^ thank you so much for the info so far!
I mostly want one for snacks for my sculpin. the small babies will be dumped in to the 40 gallon cold water tank to fend for them selves.(lots of rocks logs and plants) and be picked off as found.

 

[Fat Homer]

i think they max out at around 2 - 2.5 inches if i remember correctly?

As for babies, while they are small expect around 40 - 50 per clutch, but when fully mature i've heard they can have as many as 400 - 1000 eggs per clutch?

 

[black_sun]

yeah the self cloning ones are what im talking about,
what is there max size? and how fast can i expect them to get there from 1 inch.

^_^ thank you so much for the info so far!
I mostly want one for snacks for my sculpin. the small babies will be dumped in to the 40 gallon cold water tank to fend for them selves.(lots of rocks logs and plants) and be picked off as found.

They don't grow horribly fast and the max size for them is 5". But you'll see them more commonly max out around 4". They started breeding around 2"-2.5", which they should reach after a couple of months. I had one once, only once, start berrying at 1.6/1.7" but never again that small.

Here she is actually, tiny tiny mama lol: http://www.monsterfishkeepers.com/forums/album.php?albumid=1178&pictureid=11741

 

[black_sun]

i think they max out at around 2 - 2.5 inches if i remember correctly?

As for babies, while they are small expect around 40 - 50 per clutch, but when fully mature i've heard they can have as many as 400 - 1000 eggs per clutch?

They start breeding at that size, they max out a little be bigger. But no where near as big as the other common crayfish found for sale.

And yea, the first few clutches of a small cray will be very low in numbers with high losses. But as adults, man, if you aren't feeding them to something you'll get buried in them, lol. They have huge successful berries! 0_o;;

 

[Loves severums]

when will they start to have the eggs?

 

[Kaosu]

ok!! so i drove 45 mins one way to get this little girl...shes just about an inch ^_^
(tank pics suck bad cam + low light more to come)
yeah the 2.5 she is in is the only tank i have with a lid..sooo^_^ she has already gotten out and explored all over! going to be adding some more logs for her.

 

[joefish72]

I have marbled crays and they destroy plants. Little buggers rip the leaves off at the base and watch them float to the top. Stalk type plants get stripped of leaves then left alone. They will berry up 2-3 times a year and as already stated they quickly add up but I've found if you leave the fry in a tank together nature takes over and only about half dozen will make it.