Newbie reef enthusiast

[Stacy sli]

Hi everyone, I bought a 29gallon bio cube a couple of months ago. I cycled with 3 chromis. Have since added a blood shrimp, 5-6 blue leg mini hermits, 10 snails(no clue what kind, white shells) I bought a live rock with "mushroom coral" on it last week. Turns out that they are Yuma. I having some issues suddenly, my nitrates have gone way down after my cycle but now they have risen again, not sure what I have going on. They are almost to 10 on my test kit. Also, I think I need to put my Yumas lower in the tank. I found a spider web on one of them and can't find anything on the next to figure out what it is..I want to get my issues under control before playing with new lights, or getting new coral. Thanks for reading. Sorry for errors, on my phone. I don't have a computer anymore.
Here are a few videos. One from when I put it in, and two of the white stuff.

 

[jsker]

It seams like the tank is fairly new? You are going to have these swings in a new tank, to not be alarmed. Keep and eye on things and make one change and wait. Are the fish in the tank? You could do a water change of 10% and wait a day and retest