Hole in the Head Disease Treatment and Cure for Oscar Fish
HITH has many causes, but a very common cause of HITH is a diet heavy in goldfish. It's very simple, feeding an Oscar goldfish is a bad idea.
The carnivorous Oscar is a hearty and uncomplaining eater. They prefer to be fed a variety of live, meaty foods, but will readily eat pelleted, dead, or frozen food if offered. They grow quite large so they should be fed a high quality pelleted food and large chunk foods such as cut up prawn and earthworms. As they grow larger, they will particularily enjoy live foodstuffs such as goldfish, guppies, and worms. Meats from warm blooded mammals (e.g. poultry, beef hearts, pork, etc) were once considered a staple in the diet of all large ciclids. However, more recently it has been discovered that due to the high amounts and types of fats and proteins contained in these foods, (which do not occur naturally in a wild cichlid's diet) these foods should not be fed to cichlids. The fats and proteins contained in these foods can cause damage to a cichlid's organs and lead to dangerous intestinal blockages. If you find your fish enjoys these types of foods, be certain to feed them only as an occasional treat, not as a main course.
My suggestion? Pick one that you take a fancy to and return the other five to the store. A quarter sized Oscar is more like an infant while the others you called medium are really still very much juveniles at 3-4". Besides, these fish will grow so fast your head will spin. (You still didn't tell me what you are currently feeding these infants either?)
Oscar Fish Diseases Treatments, Symptoms | Oscar Fish Health Care
Health and Disease - Oscar Fish Forum
HITH is a deadly Oscar fish disease that also affects other cichlid fish. It may threaten the Oscars’ lives. The disease has no ascertained cause, but is treatable through administration of metronidazole infused into the fish’s food. Symptomatically, HITH begins as small while spots around the fish’s eye region and on the head. With developing time, these sports sore up, break open and deepen into the fish’s body to create distinct hues. Scientific studiesSick Oscar sick I have a 6yr old Oscar who has had hole inthe head since he was 2yrs. Recently he has developed cloudy pectoralfins with red streaks in the vein of one side. The tank is a 55gl he isabout 12" filtration is a 350 magnum,400 Emperor 280 Emp he is theonly fish in it. water changes are done weekly. filters changed aboutevert 2 weeks alternating .Change water consist of, ro/di add SeaChemcichlid salt and Alk buffer and cycle to tank each waterchange test for GH 7 KH 3 ammonia 0 nitrite 0 nitrate 60ppmI have been dosing Metronidazole last three water changes itseems to help some but at each new water change he seems to do worseagain. He acts like he is having a hard time seeing his food which allhe will eat is tetra food sticks Half the tank has about a 1/4" ofsmall gravel the other side he stays at the most is ,bare .PH is 6.9 to7.1 Not sure why he seems to do worse after water change it does looklike he has some Ich also temp is 79 would be very thankfulfor any help Thanks Jeff. He has had a good appetite until havingtrouble seeing