Hi and welcome to the forum
Any chance of a picture of the plants?
If the pictures are too big for the website, set the camera's resolution to its lowest setting and take some more. The lower resolution will make the images smaller and they should fit on this website. Check the pictures on your pc and find a couple that are clear and show the problem, and post them here. Make sure you turn the camera's resolution back up after you have taken the pics otherwise all your pictures will be small.
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Because your tank is newly set up, it won't have cycled (developed beneficial filter bacteria) yet. You should only feed the fish once every couple of days and do a 75% water change and gravel clean the substrate 4-8 hours after feeding them. You should also monitor the ammonia and nitrite levels and do a 75% water change if you have any ammonia or nitrite readings.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.
Don't add anymore fish until the filter has cycled in about 4-6 weeks time.
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What is the GH (general hardness) and pH of your water supply. This information can usually be obtained from your water supply company's website or by telephoning them. If they can't help you, take a glass full of tap water to the local pet shop and get them to test it for you. Write the results down (in numbers) when they do the tests. And ask them what the results are in (eg: ppm, dGH, or something else).
Mollies need hard water with a GH above 250ppm and a pH above 7.0. If they are kept in soft water (GH below 150ppm) they have problems.
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The following link has information about what to do if your fish get sick. It's long and boring but worth knowing. I recommend printing it out and reading it in bed to help fall asleep.
https://www.fishforums.net/threads/what-to-do-if-your-fish-gets-sick.450268/