a few question on shell'd aquatic life

[nikon70]

i have never had much luck with these but i want to know why....

crabs for one, both the small red ones and the rainbow ones
- water details all 0, ph about 7.8, temp 29C
- food, sinking crab food and live river shrimp, java moss, bog wood etc

i have read that the water needs to be high in calcium and lots of access to land, the land part i did but how the heck do you get calcium in there? if this is even true.

armoured shrimps
- again water details the same
- food - liquid food sinking alge wafers, and old food on the floor of the tank

they both last about 2 weeks then they go to the big tank in the sky

suggestions and comments please guys and gals

also one more thing - large snails how do you get their shell to stop corroding?

thanks

 

[ram man]

i guess when your talking about armoured shrimp you meen bamboo shrimp. you need alot of microbes in the water since they are filter feeders. they will also suffer from exess co2 fertalization.

 

[Balloon Fish]

To get calcium into your water you can add cuttle bone or crushed coral into your filter in a media bag or something. But if your kH is close to 5 or higher thne you're fine. When you say armored shrimp do you mean crayfish? Also all your "water details" can't be 0 if your feeding them... If they are in fact crayfish then you would want to feed them more protien like frozen krill, blood worms, etc. I'm not too sure why your "armored shrimp" died and your crabs. Did your provide any filtration for them? and how big was your tank you kept them in? more info can be helpful.

 

[FroggyFox]

shrimps also need some iodine in the water for molting...they're also sensitive to high temperatures.

As for snail shells corroding...do you mean getting all bumpy and kind of eroding away? I have a theory on that, because the apple snail I have in a tank with a lower pH and driftwood...his shell is perfectly smooth. My water is naturally pretty hard with a high pH...and the snails in my other tanks are usually very bumpy after a year or so. SO my guess is its a mixture of things from temperature to growth rate, to the pH of the water. Might have something to do with calcium...but I dont knowingly add it to any of my tanks.

 

[nikon70]

my temp in the tank is about 28C is that too high?

iodine - but they die before they have time to molt.. i think the water is quite hard and the ph is 7.8

 

[Lotus]

Most of the crabs for sale prefer brackish water, and do require land to get out onto. I'm not sure they do well in deeper tanks, in general.

28C might be a little high for crabs/shrimp/crayfish, most prefer a temp of around 22-23C.

What's the KH in your water? It could be that's it's too soft for them. If there's copper in the tank (from meds, usually), that will kill them fairly fast. The snails with chipped shells leads me to believe you may have a low KH/calcium content in your water, which you would need to supplement with high calcium foods or another source of calcium in the water column.

If you really like the crabs/crayfish, it might be a better idea to set up a small tank for one.