Just around 2 weeks ago I received 10 pcs of crystal shrimps along side with some other shrimps. I wasn't expecting the shrimps to arrive and so I have no spot to put them. I have my men clean up an old tank, fill in the filter compartments with half new and half running bio rings.
I remove the rubber band from the shrimp bags and tested their TDS. All of the shrimps are at just slightly above 100 while the crystal is above 200. I know it's not gonna be good for the shrimps with my tank water at more then 300 TDS but because it's already been half a day they are in the bag and it's getting dark, I place them in to the tank anyway. All of the shrimps except for the crystal has casualty. Some of them with eggs gave birth in the tank, while the mom dies but the babies survive. It's been more then 2 weeks now and non of the crystal shrimps died. I tested the water today and the temperature is at 28 degree Celsius with TDS at 265.
There's no soil in the tank, no fancy filtration, no plants, no special supplements only reverse osmosis water with over 250 TDS.
Shrimp's like many other invertebrate are sensitive towards heavy metal. Mineral such as copper and zink are highly toxic to them and our tap water are often fill with heavy metal. This is also why people tell the story of their shrimp would die if they change more then 15% water while all of my shrimps in my display tank that have their water change 50% every week are not harm. I use reverse osmosis water for all of my display tank. Let's say I don't trust those people that built and maintain our piping system in this country.