I have to admit I’m a bit nervous posting here because of some people just being mean and rude before, but I’m not sure if this is something I *want* to leave in my tank for the shrimp and snails I plan to get soon, or if this is a sign of something bad. I’ve never seen this type of “dirt” and “fur” *stuff* on wood in any of my tanks before.
There are no fauna in here, I’ve been dosing it with Excel daily and trying to keep the light on no more than ~5-6 hours a day. On set up I put the used filter media from my betta tank to help kickstart the bacteria, tank has been set up for just under 2 weeks now.
My snails eventually ate it all after a couple weeks, I’m pretty sure it also grows microfauna for the shrimps to eat. You can view it as a nuisance or a food source, it’s kinda up to you!
I have a hard plastic drinking straw crammed into a small poly tubing I use for spot siphoning. Might be worth to clear the light brown build up on the left side of the pictures. The rest of the lighter stuff looks like biofilm your snails and shrimp will love to snack on.
sparkpaw 
If you take a look at natural habitat, it often looks exactly like that.
I believe that it’s not a problem at all and might provide a lot of food opportunities – given that your water parameters are good.
It won’t be harmful to shrimp or snails, and honestly they’ll probably love picking through it.
I have to admit I’m a bit nervous posting here because of some people just being mean and rude before, but I’m not sure if this is something I *want* to leave in my tank for the shrimp and snails I plan to get soon, or if this is a sign of something bad. I’ve never seen this type of “dirt” and “fur” *stuff* on wood in any of my tanks before.
There are no fauna in here, I’ve been dosing it with Excel daily and trying to keep the light on no more than ~5-6 hours a day. On set up I put the used filter media from my betta tank to help kickstart the bacteria, tank has been set up for just under 2 weeks now.
Ciliates. They’re harmless and they feed on algae cells in the water column. Shrimp like to eat them.
It’s free shrimp/snail/fish food.
My snails eventually ate it all after a couple weeks, I’m pretty sure it also grows microfauna for the shrimps to eat. You can view it as a nuisance or a food source, it’s kinda up to you!
I have a hard plastic drinking straw crammed into a small poly tubing I use for spot siphoning. Might be worth to clear the light brown build up on the left side of the pictures. The rest of the lighter stuff looks like biofilm your snails and shrimp will love to snack on.
So sad that this subreddit is so harsh all new hobbyists must request other redditors to be nice 🥹
I would just siphone that off for looks anyways
Starve the shrimp a bit and they will devour it like their last meal.