New Cycled Nano Tank...dying Crabs.

Hello it has been a while since the last time I posted something here.
I come back with questions about a new project I have... a 15 gallon only fish saltwater tank.

First installation...4 weeks ago...bare tank, osmosis water, salt, filters running and heater.
Week 2: added live rock... 3 big rocks..around 5 pounds, and I filled my filters with live rock too , everything running. Started adding fish food everyday.. to keep possible bacteria alive.
Week 3: checked water...Ammonia 0, nitrite 0, NITRATE 5ppm. Went to my local fish store and the guy there advised to start with 5 small red leg crabs...not fancy at all... to see what happens and be sure tank was cycled....I put the crabs and all went out of their shells and died within 24 hours. ( my bad I thought they were sturdy and I only floated the bag 15 min. and released.
Week 4: added 20 pounds of carib sea live sand and waited to days and check water...parameters ammonia 0, nitrite 0 nitrate 10 ppm. Tried with crabs again same result. This time I floated the bag 20 min.. and used the a little bit of water to the bag every 5 -10 min... I spent 40 min. doing the acclimatation.

Salinity is 1.019, temperature 27 C.... My LFS advise this salinity... it is what they have at the store...lower risk of illness and less stressed fish.

Is my tank really cycled? why are the crabs dying?

Your help is going to be really helpful... this is my first saltwater tank.

Thanks.

 

Hello it has been a while since the last time I posted something here.
I come back with questions about a new project I have... a 15 gallon only fish saltwater tank.

First installation...4 weeks ago...bare tank, osmosis water, salt, filters running and heater.
Week 2: added live rock... 3 big rocks..around 5 pounds, and I filled my filters with live rock too , everything running. Started adding fish food everyday.. to keep possible bacteria alive.
Week 3: checked water...Ammonia 0, nitrite 0, NITRATE 5ppm. Went to my local fish store and the guy there advised to start with 5 small red leg crabs...not fancy at all... to see what happens and be sure tank was cycled....I put the crabs and all went out of their shells and died within 24 hours. ( my bad I thought they were sturdy and I only floated the bag 15 min. and released.
Week 4: added 20 pounds of carib sea live sand and waited to days and check water...parameters ammonia 0, nitrite 0 nitrate 10 ppm. Tried with crabs again same result. This time I floated the bag 20 min.. and used the a little bit of water to the bag every 5 -10 min... I spent 40 min. doing the acclimatation.

Salinity is 1.019, temperature 27 C.... My LFS advise this salinity... it is what they have at the store...lower risk of illness and less stressed fish.

Is my tank really cycled? why are the crabs dying?

Your help is going to be really helpful... this is my first saltwater tank.

Thanks.

You are probably gonna get a lot better response if you try again in the Saltwater Forum. Although I am sure there are folks here who have experience with both.

 

First of all, unless you got live rock that was already cycled in another tank it's not very likely it would cycled that quickly
Second, putting live rock in the filter only works if it's getting good flow, if not then the established bacteria begins to die off and will trigger a cycle.
Third what are you doing for powerheads/wavemakers in your tank? Marine tanks need current in addition to filter flow
Fourth, what test kit are you using? API is notoriously unreliable for Ammonia (ie can show false positives) and it's nitrate test is difficult to tell the difference between 10-20, 40-80, etc.
Fifth, as you already know the acclimation time was probably insufficient and I would definitely suspect that as well.

 

First of all, unless you got live rock that was already cycled in another tank it's not very likely it would cycled that quickly
Second, putting live rock in the filter only works if it's getting good flow, if not then the established bacteria begins to die off and will trigger a cycle.
Third what are you doing for powerheads/wavemakers in your tank? Marine tanks need current in addition to filter flow
Fourth, what test kit are you using? API is notoriously unreliable for Ammonia (ie can show false positives) and it's nitrate test is difficult to tell the difference between 10-20, 40-80, etc.
Fifth, as you already know the acclimation time was probably insufficient and I would definitely suspect that as well.

Thanks. Since it is a small tank, and has two power filters I thought water flow was enough. But I will put a small power head.

About water flow in the fikfilt I think is fine...and live rock I used was already established as it had long time in the aquarium I got it from. I even got rocks from the sump my LFS has for its tanks.

Isn't live sand not enough for boosting cycling?

What woukd be the problem then?

 

Were you testing every other day for the first week? Usually that is recommended with rock that has already been cycled. Also how long was the rock out of water? The longer it goes out of the water the more die off you have.

 

I checked two days after putting the rock and there was ammonia ...it was high...then I checked after three more days and ammonia had decreased...then I xhechec weekly.

Rock was out of water just the transit from the store to home...

 

Some people claim that live rock is okay to be out of water long enough to be tranferred home, but I firmly believe that live rock should be submerged for all but the direct transfer from one saltwater source to another. This ensures a vritaully negligible die off. When I transferred from my old 36 gallon bowfront I had to take the time to move my old tank out of the way and slide the new one in due to space limitations. What I did was drain part of the old tank water out into 5 gallon buckets and then when I was ready pull out the live rock and put them in the saltwater in buckets for temporary storage, I then moved and transferred other items and slid the new tank into place, once the new tank was ready for the rock I added it and then promptly added water to resubmerge it. The result was rockwork that had no significant die off and worked well. I added 50lbs of extra rock after cycling it in a separate garbage can and rolled it over to the new tank for transfer and once again no problems.

Sorry, you had to go through another cycle, but I'm hoping the die off will be minimal and you will be back on track before too long.

 

Thanks for everybody's response.

So is my tank cycled or not? How to know?
What should I do next?
I'm starting week 5 ...

 

Thanks for everybody's response.

So is my tank cycled or not? How to know?
What should I do next?
I'm starting week 5 ...

Not cycled I would say give it 1 or 2 weeks until you could put
a hermit crab