A serious ammonia problem

[rivulet9]

Keep looking for any leftover food and remove it, that's still a source of ammonia. Also, give your filters a good cleaning, the water's still passing through them and it's possible that's where the issue is.

[fleeton]

I've had my share of Eheim feeder issues too, so I've learned not to rely on them. My fish are currently on a little vacation of their own, fasting while I'm away for a few days. I'm not too worried, they'll be fine. I've found that before leaving for a trip, it's a good idea to lower the salinity to around 1.023, secure any corals, and just let the tank evaporate naturally. I also switch off my skimmer as a precaution. If you do this, you'll minimize the risk of problems.

In your case, I'd do a large water change right away, remove as much uneaten food as possible, and then just give the tank some space. An established reef like yours should be able to recover from this.