Tlindsey

You don't need to worry about target feeding if that what you meant by how do you get it to them.

The pellet will sink to the bottom. @Louise02

Your aquariums look very nice in your new apartment.

I would personally add fluval bug bites to that rotation.

That food will be fine for them. @Louise02

It's definitely the uneaten wafers causing the issue. If you don't notice the Ottos eating the wafer you may need to try another brand. I suggest doing a water change and don't feed for a couple of days retest your water parameters. @Scaperoot

Oh that's great. I tagged a member hopefully he will chime in with his thoughts. A standard 40 gallon would be great.

@tolstoy21

What about the stiphodon goby. They are a small species.

Yes I would do what I stated earlier or place biomedia in a bucket or tote with water from your aquarium that's if you plan to setup another aquarium. If you don't want to do neither than rinse off and store in box or bucket dry area of your home.

What do you have your fish in right now? I would place biomedia in a mesh aquarium approved bag and place it in with your fish.

Improving the hobby will continue to difficult to do. Various reasons some don't do research. Others treat fish as ornaments and not living creatures. Big box chain stores don't train their aquatic department employees so some are doomed from the start. Some are lazy and won't do their own research prior to setting up a aquarium. Also like stated some bad fishkeeping videos. Tbh I personally lost lot's of fish due to lack of resources no internet but got better when magazines like Tropical Fish Hobbyist appeared in lfs's. I started to get better and kept some hard to keep fish Marbled Catshark's, and the Seahorse.

Sorry for your loss. I personally had a bad experience with peroxide.