Threre could be a few reason why you tiger keeps dying on you.

1) They could be stressed out if they die after you just bought them
2) Tiger shrimps life span is around 1-1.5 yrs only. Could be that your shrimps are already old when you bought them.
3) Could be that your shrimps are already sick when you bought them. You can identify this by the colour of their body which is milky in colour. A healthy one have clear see through body. Not all milky coloured body will die but if you are unlucky, those that might not recover will die off. Best to buy smaller shrimplets as they are more hardy and less easy to stress out, not to mention you'll know that they are young.
4) Dont buy shrimps that just arrive in LFS. Normally a big percentage will die off due to the stress of transportation. Wait it out before buying.
5) If none of the above applies, then water parameters are more likely the case. Certain shrimps are more prone to be stress by different parameter, so you'll need to find out what parameters are suitable for your shrimps. My bees are doing well in my tank while they dont survive in Dom's tank????? I cant seem to keep green while Dom's doing great??????

Shrimps, funny creatures, they are!!!

Cheers,

KG

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