Why is my fish not eating, has yellow poop, and a growth under eye?

The fish pictured are incompatible in the same tank. Angelfish (black ones) are tropical fish and do best in temps between 73 F and 84 F. Goldfish (white and orange) are cold water fish thriving in temps between 65 F and 72 F. It also appears as if one of your angels has some damage to a tail fin. This is typically due to fin nipping by other fish. You will need to remove either the angels or the goldfish and place them in a different tank. Check the water chemistry for elevated levels of ammonia or nitrites. This can occur in an uncycled tank or a tank that is overstocked. Partial water changes (30-50%) daily can decrease toxin levels. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Confirm your filter is rated for at least twice the water volume of the tank, especially for the goldfish. The links below provide additional information for care of angels and goldfish. http://aquariumtidings.com/angelfish-care/ http://aquariumtidings.com/all-about-goldfish-how-to-care-for-a-goldfish-fish-at-home/

Check the water chemistry and temperature. Use a home test kit or submit a water sample to test fro elevated ammonia or nitrite levels. Most pet stores will do this for free or for a small fee. Partial water changes can be done, if indicated, to stabilize chemistry and improve or maintain water quality. Ideally, you want 0 ppm ammonia and nitrites with nitrates at 20 ppm or less in a non-planted tank or 40 ppm or less in a planted tank. Use only aged or conditioned water that is temperature matched to prevent stress or shock. You'll need to keep the temp at the upper limits for Red Tails in order to keep the Angelfish comfortable. That would be in the 78F to 80 F range. Both have similar pH requirements, 6.8 to 7.5. You can fast the Angel for 2-3 days then feed bits of cooked, shelled green peas. This will usually resolve constipation and bloating. Pristine water quality may resolve the patch on your shark. Recommending a medication without more information or a clear image would be risky to the stability of the tank's nitrogen cycle. You can use plain aquarium salt (NOT table or Epsom salt) as a general tonic. It will reduce stress, improve gill function, may treat minor infection and aid in recovery. Dissolve 1 tablespoon per 5 gallons of water in a cup of tank water and gently pour it into the tank. Treat for 10-14 days then reassess the condition. A note on tank size: Although the two fish may be fine in a 15 gallon tank now, you will likely need a larger tank as they mature. Red Tails can reach 6-7 inches and Angels can reach 6-8 inches. At adult size, a 15 gallon tank will be insufficient and could lead to some aggression from either fish.

This is a quite generic but concerning presentation. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. Clinical examination should always include a water quality check, even if you have done so already. Water testing should be performed with a quality test kit, measuring NH4, NO2 and NO3. High ammonia levels, PH imbalances may be responsible for these signs. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

Check the water chemistry. This is done using a liquid home test kit or by submitting a sample for testing. Most pet or fish stores will do this for free or for a small fee. Ammonia and nitrites should be at 0 ppm and nitrates can be 40ppm or less. Partial water changes can be done to stabilize chemistry and maintain water quality. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Try soaking food in garlic juice to stimulate the appetite. A 2-3 day fast followed by hand feeding bits of cooked and shelled green peas or spirulina may also promote regularity.

Perform a partial water changes, 30-50%, using conditioned water. Dissolve 1 teaspoon up to 1 tablespoon of Epsom salt per gallon of water in a cup or two of tank water and gently pour it into the tank. This will work as laxative. Fast the fish for 3 days, then start feeding bits of cooked and shelled green peas until defecation and appearance are normal. You can also add metronidazole at 200mg/20 gal to the tank. Repeat the water change, salt and metronidazole every 3 days for 3 cycles. Be sure to treat only the amount of water being replaced with salt and not the entire tank volume. Remove the carbon filter insert during treatment as well.

He may be dealing with some swim bladder issues. The swim bladder is what keeps a fish upright and controls buoyancy. Infection, poor water quality or constipation can affect the swim bladder. Perform a water change. Use aged or conditioned water that is temperature matched to prevent further stress or shock. My choice for conditioners are AmQuel and NovAqua. You can purchase them in most pet stores or fish stores. Bettas are warm water fish and do best between 78 F and 80 F. Anything below 75 F will be stressful. A small tank heater may be necessary to maintain proper temperature. Dissolve 1 teaspoon of plain aquarium salt (NOT table salt) per gallon of water in a cup of tank water and gently pour it in. This will act as a general tonic reducing stress, improving gill function and treating minor infection. Change the water daily to maintain quality and dissolve just enough salt to treat the water being replaced. Fast him for 3 days, then offer small bits of cooked, shelled green peas until defecation and swimming are normal. You can soak the bits in some garlic juice to stimulate his appetite and boost the immune system. Transition to a quality pelleted diet and fast for one day each week to maintain GI health.

These are quite concerning but generic signs. The approach must be logic but quite radical at the same time. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. Clinical examination should always include a water quality check, even if you have done so already. Water testing should be performed with a quality test kit, measuring NH4, NO2 and NO3. High ammonia levels, PH imbalances may be responsible for these signs. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.