Chicks dying!

[slmwatts]

Hello, I finally bought baby chicks this year from a reputable supplier. I bought Prairie Bluebell Eggers, Marans and Easter Eggers. I started with 12 and lost 5 in the first few days. I think that was due to temperature problems. Now I’ve got that figured out and bought more chicks. Had them one week today and three have died (1yesterday and 2today). One more sounds like it’s got respiratory issues. Edit: I’m feeding medicated starter and they are 1-2 weeks old. They’ve all had the Marek’s vacc. Why are they dying?! I’ve been adding Poultry Cell to their water off and on, also tried a couple days to add ACV as the supplier suggested. Any ideas? We do have stick tight fleas on the big chickens but the chicks seem to be ok, not too many fleas- can I use DE in their pen?

 

[50-45-1]

So, are the chics in a brooder inside the coop with the adult chickens? That should not be a problem but trying to envision your set up.
What type of heat source are you using? How big is yor brooder and does it have good ventilation?
What type of beddng in brooder?
A picture of it may help us spot any problems.

 

[slmwatts]

It’s an open air cage 4x4feet with a 1.5x1.5’ box inside for shelter and a heat lamp on during night because temps get down to 70F. Day temps are 95+ so no heat lamp then, and they have the ability to get away from it too. The bottom of the cage is dirt and sand with some very fine gravel. Big chickens are in another coop nearby at night and free range during day. The chicks are dying at random times. I’ll check them early AM and all are well and then mid morning one’s dead, or even later in the day.

 

[50-45-1]

So fine in the morning, then deaths during the day.
Is their cage in the full sun during the day? I know you have the shelter box but is that the only shade?
I would switch out the base, maybe there is something bad for them in the soil. Maybe they are eating to much of the gravel. Put them on wood shavings for a time and see if you still loose any.
It sounds like you are doing everything right.
Chick starter is always avaliable right?
Lots of fresh water too. Sometimes acv can discourage them from drinking.
Keep us updated!