Hundreds of these and thousands of those.

Sorry if the pictures are bad quality really wish I had some petri dishes laying around but I mad due with what I had, and sorry for the mess in the second picture it was cleaning day and it was the easiest time to see the bugs. On the top of the first one is a feather type deal.

 

first pic can't say and 2nd is a nudibrach of some sort.

 

Second one looking copepods which is good news. First I can not tell. Maybe if you give us more info about it we can help.

 

looks like some sort of sponge. I have those all in my refugium and baffles. The second one is a pod. Both, if I am correct they are harmless and good for your tank.

 

First looks like either a spaghetti worm or a peanut worm.

Perhaps put white or white paper behind the petri dish for contrast

 

the first one looks like a mini sponge. i have tons in my sump and refugium that stick to glass and rock that look just like that. I've been told they are good filter feeders to have.

 

second picture looks like pods to me, nothing harmful.
if you can confirm they look like these (see pic), you're good!

 

nice high res photo that's exactly them. So if I have plenty of these should I be in the clear to get a mandarin? Been waiting for a while till I was sure that I could support them. And the second one is a cm or so long white in color with a feather type deal coming from the top they attach everywhere in the sump and on my return locline. They're stationary and haven't seen them move. Hope this helps

 

Those are Munnid isopods, which feed on algae and detritus (those are females, BTW). As for getting a mandy, it kinda depends on how large/mature your tank is and how long it has been running. Mandies pretty much forage all day, and will decimate a small population of pods quickly.

The first pic is too fuzzy, but going by shape and color, I suspect it's a bristleworm, as they can retract to a very short length and stretch out to their full size.

 

so that's what mandarins eat? Fascinating!