Ok its 4 things,

first i have feather dusters multiplying in my tank as of today i counted at least 15 new little ones in my tank and I'm guessing there are more ( should i get rid of the and if so how or should i let them grow and sell them to pet stores)

Second the are the little tentacles in my tank ill try to explain how the look and what they do because i have no clue if the are good or bad. these tentacles come in sets of two or three and the grab my sand and create a little sand tunnel while they grow, the tentacles are clear and about and half an inch to and inch long.

this next one i think is because of my snail so i'm not too worried but i get what looks like spider webs in my tank is certain areas, but if i'm wrong tell me

and last i have this white algae growing on my back wall and it looks like when you get a strong current through you hair and it waves that what is does every time the filter passes over it.

help me please because i just made a custom stand for the sump i'm building and i don't want to stress my tank out to much if there is already stress on it.

first off in my opinion the small dusters probably came with the rock. they are not a bad thing. they will take years to grow big enogh to sell +they help clean your water. the tenticals are probably small worms . not a bad thing they clean your sand and do no harm. those small webs i think mabie your calcium is to high.check it. also bacteria do water changes with clean water.