Two months ago, I added a Clown Goby to the tank. Over those two months, I never saw him actively eat anything. I thought he had to be eating something since he didn't die within the first month. However, over the course of the second month, he became very skinny with a sunken belly and visible lateral lines showing. After some research, I decided to set up a Quarantine Tank (QT). This way, I could keep him somewhere which would allow me to try different food types without the other fish hogging it all. Also, there is the possibility I may have to medicate him for internal parasites.
Last evening, my shipment of food and medications arrived. Tonight, I moved him into the QT. In the pic, you can see that the QT is minimally equipped. I have a Hang on the Back (HOB) filter and on the right side is a filter sponge with an airstone underneath it. I soaked both filters in my sump for 4 weeks (I have been worried for a while). Leaving them in the sump gives time for bacteria to collect in the filters to aid in keeping the QT water quality as clean as possible. I am planning on doing water changes every other day to prevent ammonia and nitrites from rising. The PVC piece on the left side is a place for timid fish to "hide" if they so desire. Finishing off the equipment is a heater in the back along with a thermometer strip along the front glass.
My plan is to keep Fluffy in the QT until he fattens up again and I can transition him to the food types I feed the display tank. To start this journey, I will be soaking Formula One flake food in Selcon. This creates a "hunger inducing" scent in the flakes. I tried a little bit before typing this and I watched him nip at some of the flakes. Huge success in my book to actually watch him eat a little. In addition to the flake food, I have some Anti-parasitic caviar which I will feed once a day. This is to provide a different food source as well as treat the possibility of internal parasites. The last step on the current plan is to add Vita-Chem to the water every week. This adds vitamins to the water which will absorb through Fluffy's skin.
A huge thank you to Oxy for recommending the food/medications to try.