ph and black marks

Question
QUESTION: I have 2 goldfish in a 55 gallon tank. The ph is 8.0. I can't seem to get it any lower. Is that safe for goldfish? Also, they have big black marks under their belly and on their sides and their fins have split. One has had this for at least 8 months, the other one just recently developed it. His fin turned completely black and the other one has turned some black. They do swim around okay and eat well. The one that recently developed the black marks sometimes sit at the bottom of the tank in the a.m., but he also has swimbladder disease. Should I treat them with a parasitic food or anti-bacterial food or will this do more harm than good.

ANSWER: Goldfish turn colors (especially black) for a variety of reasons. Sometimes it is stress related but mostly it is almost a genetic enhancement and not to be worried about.  For the swim bladder... I would feed him nothing but brine shrimp for a week and see if it gets better.  He probably has a small obstruction. Do you feed pellets???? if so... I am pretty certain that is what is wrong with him.  If the brine shrimp does not improve the swim bladder issue then I would consider the parasitic medication .... The pH... Is your tap water at 8.0 pH too????  keep me posted please... dave

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QUESTION: The tap water is 8.0 after I leave it out overnite and test it. If I test it right away, it is 7.6 then starts to fade and goes cleasr, within a minute or two in the test tube. I feed the goldfish a gel based food and they seem to do okay with that as long as I do not over feed or feed them any pellet food. As for the black on his body and fins. If it is normal how come his fins are splitting? I keep the tank water about 2/3 full to help the swimbladder. Thank you for your quick response.

Answer
There are no fungal diseases that are black... fins split due to water chemistry, dietary issues, and medication, etc.  I would suspect that it is a combination of the pH and stress, etc.  I can only recommend that you feed the fish brine shrimp to see if he gets any better.  Medication does as much harm as it does good in fish tanks so I do not want to just offer up a medicine as a cure all.  This is a problem that occurred over time and time will help you fix it.  The brine shrimp will help a lot too.