It is probably normal. From my experience it really varies a lot with them. You might post a picture of you can and others more experienced might be able to notice anything that would concern them.
I have a heat bulb in with them at one end and it's high enough so the can't hit there heads on it. They get feed and water 24/7 and fresh water every day. I do a treatment in there water every other water fill up. Water time no not yet its been cold here in Pennsylvania so I haven't been able to get a pool for them to set up yet. Treats are a a mix of meal worms and a couple other bugs.. I will get a picture and try to figure out how to post it on hereMy ducks have lots of runny poo but they drink and okay in water all the time
My thoughts it’s probably nothing ti worry about.
You can share a picture if it and give some back info
Do you provide heat ? If so how hot ?
Do they have access to feed abc water at all times ?
What is there brooder set up
How often do they get fresh feed and water ?
Do they have water deep enough to dunk their heads ? Do they get bath / pool time ?
What feed are they on ? Do you give treats ? If so what ? Do you provide grit to help digest any treats ?
Sorry for all the questions but it will help us to help you
If giving those treats I would also set a bowl of grit out
I do give the grit I did see I forgot to mention that
The Hydro-hen is nice stuff I have it here and use it occasionally, like if they are weak or sick or stressed out, but they don't need it all the time, The bag says they can have it alongside fresh water ot if given as only source of water then only for 12 hours and back to just water, however, it is recommended to Offer it for no longer than four to six hours per day, for a week.
