Dubias and tap water

This may be a no brainer and may not even be the cause/solution to my dubia issue.

I had been giving my dubias city water (not well water), in a paper tower and had a fair amount of die off. I would wring the paper towel out so that there would not be excess water and would replace daily to keep mold from growing.

I had been working at locating (and still may not have found the solution) a reason to why I was having dubia die off. My other conditions seem normal but I will go ahead and list incase anyone sees issues.

ventilated 20ish gallon Rubbermaid tub
seed germination heating pad on the bottom of tub (temp gun the bottom of the tub at around 95 degrees, though spots vary in temp)
every other day food is changed (oranges/carrots) also dry cricket feed is provided on top of fruits
vertical egg trays for hiding
normal humidity is around 35% (though I do run a humidifier to get humidity around 50%)
housed in spare bathroom, bathtub, tub never moved, shower not used
had been providing daily, wrung out paper towel with tap water for drinking (have since stopped)

I haven't had but a couple die offs lately since stopping to give them water from the sink. My main question is has anyone had any issue with feeders dying off due to city water with chlorine? I stopped due to roach die off but if it was causing roaches to die, wouldn't want my dragon also eating a roach that had ingested chlorine. Any experiences or info?

Last note, no longer watering roaches at all, giving them plenty of fresh veggies to get their hydration

Thank you!

I don't imagine the tap water would cause a problem for them. That said, I think you'll be fine just giving them fresh veges and fruit. I've done that for years and my colony is thriving. They love squash and orange slices which are very hydrating.