That's quite a few losses.I’ve ordered for the water what you recommended will be here for pickup tomorrow. We’ve gone from 21 to 13 rapidly
Can you post some photos as requested previously?
Where did the chicks come from?
What breeds are they?
How are they housed?
What are you feeding?
What are the symptoms you are seeing?
There's no need to start another thread - just please give more information and photos, we will try to help you and can tag in more help if needed.