Cray Questions

[fl4ian]

I was looking for some Marbled Crays (marmorkrebs), but heard that they might be rough on plants. Can anyone verify this?

Also, if they do, what are some other cray's that are friendly/passive, that won't eat my fish. The CPOs?

Any suggestion and knowledge would be appreciated.

---todd

 

[Wycco]

I'm not an expert- but yes, I believe that most non-dwarf crayfish attack plants... unless one of our cray-experts can tell you otherwise- it is safest to assume they do.

CPOs and in fact any of the dwarf Cambarellus crays (such as Shufeldtii- the dwarf cajun Cray) should be mostly safe... I say mostly- because they leave healthy plants alone but they do eat damaged vegetation (and love squash BTW).

I had a fragment of guppy grass floating around that recently had been broken off during tank maintenance... it eventually came to rest trapped in the Java Moss...

A Dwarf Cajun proceeded to pick it up and eat it- placing the broken end into it's mouth. I've never seen one attack a healthy undamage plant though... and I spend way to much time staring in the tank!




Regarding dwarf crays "Peacefull" is a relative term- people call them peacefull- I think "harmless" is a better word- they are actually quite quarallsome little beasties- far from peacefull, friendly or passive.

When there is food in the tank they make sure to chase away all the fish- giving the Corydoras a nip on the bum and waving their claws at passing shrimp...

... they have a huge but amusing attitude problem to say the least... it's one of the things that make them so charming...

BUT- they are mostly harmless- their small claws are incapable of harming fish or adult shrimp... new born fry and shrimplets might not fare as well. I've seen absolutely no damage to my fish from the Crays.

They will defend themselves when approached (someone comes near them) - but unless food is in the water- they don't actively go out seeking confrontation... I've noticed everyone has learnt to avoid them.

They will attack snails on occassion... bladder snails and ramshorns are at risk... MTS and QM are safe- as are adult apple snails... I did have to rescue a baby spixi from one once and I have seen one provoking a Tylo.



Overall though Dwarf Crays are fine for a peacefull community tank- undamaged plants are left unmolested- and unless you are a new-born or a pest-snail you're safe.



People HAVE kept larger Crayfish with fish- and I know some species are better than others (although I couldn't tell you which)... it's always a gamble though- and I wouldn't risk any expensive or prize fish with a larger Cray.

There may be some that are plant safe too... I don't recall reading of any though... but there are LOTS of species of Cray.

 

[fl4ian]

Wow. thanks for the info, Wycco. very helpful.

 

[msjinkzd]

wycco that was an excellent post and spot on.

Marmokrebs will relish eating your plants as an aside.

This is an excellent description:

Regarding dwarf crays "Peacefull" is a relative term- people call them peacefull- I think "harmless" is a better word- they are actually quite quarallsome little beasties- far from peacefull, friendly or passive.