Also, I forgot to say and ask. Very few of my neos are 1 color. Most have a clear area where organs are, then circled by its color. Let me share a picture.  This shrimp seems like it's black but head area is clear. Most of my blue neos were like that.  Now this one is one of the few that grew up 1 colored, and I have no idea what freaking color it is. I didn't buy it, so I'm sure it's one of my first babies from last September/October. But parents were both blue neos, and it doesn't have a clear area where you can see organs. Is that normal?

Thank you for all the help. I believe the issue was a bacteria. Deaths have stopped so far. Shrimps are very active, they keep molting and there's still 1 berried female. I keep doing water changes until it cycles, and half the tank doesn't have the fuzzy white thing anymore. The other part does still.

I haven't been able to find an ammonia test kit so maybe that was my problem but I woke up to no dead shrimp. Before I do a water change I want to make sure my water I have is correct with water parameters and GH and KH  especially. I did cycle my tank and it should be fully cycled by now.    Thank you all!

Sorry to hear you lost some shrimps! How big is your tank and how long has it been running? Did you do the 'cycle'? When doing a water change you should drip the new water into the tank. That will illiminate the temperature difference problem and any difference in parameters between the two waters. When acclimating new shrimps you should drip acclimate them as long as you can, the longer you do that the better chance they have of survival. You will need to match the water temperature to that of the tank by floating the container with the shrimp in the tank once you have stopped dripping, before adding the shrimp to the tank! The parameters you have I would think are acceptable so I would stick with tap water if that is what you are using, for now. RO water is ideal but you will then need to buy GH/KH+ to add the minerals. As I say, I would hold off using RO/distilled water for now until we can pin point the problem. If your water has a green tint to it that may be an algae bloom? A white tint is usually a bacteria bloom and I have only seen that whilst a tank is 'cycling'. I think an algae bloom will mean there is less oxygen in the water as the algae absorbs it?????? Overfeedinng is very common. It will depend upon the size of the tank and how long it has been running etc. With only a few shrimp there may actually be no need to feed additional to the natural biofilm of the tank. As shrimps are feeding all day on biofilm it is usually better to see additional food as just a treat and feed very sparingly. Overfeeding with shrimps doesn't usually mean that the shrimps over eat, it usually means  too much uneaten food polutes the water and if you have green tinted water, algae bloom, that may be why? There usually comes a time, if you are lucky, that there are too many shrimps in the tank for the biofilm to sustain on its own, so as the population grows feeding may become more necessary. Shrimp don't usually hide unless they are new to the tank or there are fish etc (even then they will usually adapt to them) or as JayC says, their is something wrong with the water quality?  Simon

Sorry... this was meant to be partially sarcastic. I mean it's a bit sad but I don't really mind all too much. Yeah they're like that, with those big mouths.