Bugs in tank

[EvilMuffinOverlord]

Hi. So, about two weeks ago, I was given a ~3 month old beardie. His previous owner had been taking pretty good care of him, from what I was told and could see, but simply didn't have time to handle the young beardie and wanted him to go to someone who had time and better knowledge of lizard behaviors. (Which I have some experience in, and my sister has a fair amount of experience in and is helping me while she's home on break)
On the first night, we saw a couple bugs in there, killed the ones we saw, and cleaned the tank, assuming that would be the end of it.
Now, last night, I had turned off Artemis' lights, while my bedroom light was still on. I look over... And there's this little bug crawling on the inside wall of the tank. I obviously reach in to try and kill it, and a few MORE appear, seemingly out of nowhere. I get Artemis OUT of the infested tank and into his travel tank, and my sister and I haul the tank and all of it's accessories into the bathtub to drown them, and then for good measure we took the shower head and blasted the corners, everywhere we could think of. A few went down the drain, and we left it overnight to dry.
This morning, we found a few live ones, some of which that had gotten out and into the main part of the bathroom unscathed. My mom poured boiling water into the bottom... And we saw ANOTHER live one crawling around the bottom after we poured it out.

I guess I have a few questions? What could these things be (I will post a picture when I get a chance)? Have they been living in the lining of the tank? I take the food out of the tank at night, so what are they eating? Has anyone else experienced tank bugs like these?

Anyway, we've thrown the tank away now, and we have a few temporary containers set up until the new one comes in next week... Feel free to ask any questions about setup and what not if you to, I'm happy to help if it means figuring out anything about these creepy bugs that have been bothering my lizard!

 

[EvilMuffinOverlord]

Here's a picture of the nasty thing... The only one I managed to get a picture of was the one crawling around in my bathroom, and the picture quality is bad due to the movement.

 

[VenusAndSaturn]

Sort of looks like a small turkish roach, though not entirely sure but definitely some sort of roach. If it is a turkish roach then the owners probably never cleaned the bugs out and just let them roam around. They're commonly used as feeders for reptiles and inverts i believe, from what ive heard instead of dubias many people use the turkish roaches for their spiders because they trigger a better feeding response because unlike dubias they dont just sit around.