The Tank is over a year old with some larger corals, nitrates and what not are at 0, ph 7.8 salinity 1.027,
I dont think its about trying new foods at this point, it feels like he has just given up
I hate to be a "Debbie Downer" but fish don't metabolize fat well. Once they get to a certain point, they utilize liver for energy. At some point, even if they start feeding again, their liver is shot. This fish is also sunken in the back as well, indicating long term starvation, before you even got the fish.
There is a method for tube-feeding fish, but it is tricky to do on smaller fish like this, and you really need a fish anesthetic to do it correctly. Here is some info about it though:
The tube-feeding process can be employed to give the fish food energy during the time it is anorexic. In some cases, this gives the aquarist enough time to determine a permanent solution. This process uses simple equipment—a syringe and a flexible plastic tube. Feline urinary catheters or avian tracheal tubes can be used for small fishes. Larger fishes can be fed using standard airline tubing attached to a large syringe. A Luer-lock syringe will hold the feeding tube more securely to the syringe body. Placing the tube is easier if you first bevel the end of it. The tube should have marks on it at regular intervals so you can more easily judge the depth of insertion.
The basic food recipe is to create a liquid that will easily pass through the feeding syringe and tube but is thick enough to carry a high amount of calories to the animal’s digestive tract with the least amount of water. It is best to prepare this slurry in a blender, using components of the fish’s normal diet.
The amount of food administered at one feeding is generally 2 to 4% of the animal’s body weight, just enough food to cause a slight distension of the animal’s belly. In most cases, the use of an anesthetic, such as MS-222, is required to sedate the fish so the tube can be inserted. Holding the fish on its back, gently insert the tube into its mouth and try to locate the esophagus. If you are too far to one side or the other, the tube will miss and emerge from under one of the gill covers. Once in place, gentle pressure on the syringe plunger will move the liquid food into the fish’s stomach. Once fed, the tube is gently withdrawn and the fish is moved to a recovery tank.
Spontaneous regurgitation is the most commonly seen problem, though there are also reports of people accidentally rupturing the fish’s digestive tract. Like any medical procedure, there are subtle techniques for this process that need to be learned through practice—so please do not expect to read this basic introduction and suddenly be proficient at tube-feeding fish.
Jay