How do you tell if you have bad bug/parasites

[RAIN CITY REEF]

I've noticed so many different bugs in my tank lately i've identified some but a lot od them I can't find anything. I've looked at so many pictures and descriptions of different types of bugs and parasites common in reef tanks but it's so hard to identify them. All my corals are doing super good but I see some of them go on my polyps and walk aroud on them but none on my LPS's. I've been doing coral dips with Coral RX when i get new corals for almost the whole time I've had my tank (9 months) just want to know how I can tell if I have a bad parasite/bug. Thanks for your help

[Reefing Madness]

If you catch them eating one of yoru corals, its a bad bug. Like you said, there are a ton of them out there. you just have to watch your system.

[RAIN CITY REEF]

Is it pretty noticeable when they are eating the corals? Do they close up? I thought amphipods were bad a couple months ago because I had a huge nitrate spike when I moved my tank to my new house and a polyp was dying and I noticed that the amphipod was eating the dead polyp, it was hella weird. Thanks for your help!

[Reefing Madness]

You will see lil pieces missing on the coral, and they will close up, and be ticked off. Watch the foot of the corals.