Petshrimp.com Discussion Forum

HEY ALL!

I'm absolutely new to crayfish and to aquarium keeping in general; the only things I know I've learned from the materials & methods of research articles I've read. After one round of crayfish (~24) I've finally gotten the hang of the general housekeeping things. Let's say I learned the hard way about cycling water, ammonia levels, proper oxygenation and most of the other aspects of crayfish keeping. I have been able to successfully keep 9 crayfish for the past 3 months.

So now I need to learn how to breed them. I work in a crustacean physiology lab at UNLV and my goal at this time is to measure gestation periods in different environments to compare, the end result of this project is to figure out why the crayfish hatch when they do. There's some speculation around this topic, but not much research so I can understand if some feel it's a silly experiment.

I started the crayfish off in larger (~30 gallon) tanks and housed them 3 to a tank which seemed to work out pretty well. I have recently (this morning) converted one of the tanks into single housing. I've attached a few photos below.

I don't really have any questions at the moment, but wanted to introduce myself a bit and share a few photos with anyone who's interested. I am ALWAYS looking for some input on how I can better care for these organisms, so if you have any thoughts or ideas I'd love to hear them.

Thanks for the introduction and the pictures! Las Vegas must have pretty "hard" and high pH water. Care to share your water parameters? (primarily kH/alkalinity...but pH and TDS/conductivity would be interesting, too.). I found that keeping inverts at low alkalinity levels is the key for long term survival and successful breeding.

Testing water from existing aquariums (not the new "condos" I made the past few days) with master kit;
89.5 ppm KH
pH is a little questionable.. I'll post a photo of my testing results later.
I usually use the master test kit for "more reliable results" but I also used a quick dip that I had a set of and these were the results from it..

Nitrate (NO3) 0-20 ppm
Nitrate (NO2) 0 ppm
GH 300 ppm
Chlorine 0ppm
KH 80ppm
pH 7.2

Yeah...the pH seems very wrong unless you somehow have huge amounts of CO2 in your tank. I'd get that kH down to almost nothing (about 17 or less is actually perfect but 10-30 is good enough) while at the same time buffering the water with some limestone. that's what I do anyway and it works.

Are you saying limestone will help with the KH as well as pH?
It was difficult to correlate the color.. Maybe it makes more sense to you? I followed the directions to the T.. The following photos I attached were ones I took of the test results yesterday.
I did a partial change this morning so I'll test again when I come back from class.

Thanks again for all your input, I really appreciate it.

I'm not a big fan of those dip tests, but the drop test seems to show a pH of around 8....way too high for inverts in captivity in my opinion. pH is directly dependent on kh. The lower the kh the lower the pH.

I have some pH down that I'll toss in the next time I check up on them.
I asked a guy in my lab who said that we should have some limestone around that I'll put in the tanks too.
I'll post an update.

Don't use the pH down in the tank. It's meant to be used when you prepare water for water changes outside a tank. Sudden pH changes can harm the animals. Plus...immediate pH measurements after using pH down are worthless as carbonic acid is produced by most of those products which needs to be aerated away (with an air pump) before you have more or less accurate pH measures. Again...don't worry about the pH...use the pH down to get the kH to about 1 and the pH will follow.