Goldfish hardly moves and has dark spots all over.

Question
QUESTION: Please help.  I returned from vacation today and my goldfish was huddled up in the top corner of my tank with dark spots all over.  She hardly moves at all.  She was on a feeder when I was away.  I changed the tank today when I got home but it didn't seem to help.  Please help fast, it doesn't look good!

ANSWER: Hi

It is one of two diseases or both coming as a result of water pollution

Ammonia Poisoning
Ammonia poisoning is caused by the buildup of organic waste due to overfeeding, fish or plant deaths and decay, or improper cycling. Ammonia poisoning especially occurs when the pH exceeds 7, when benign ammonium becomes ammonia. Symptoms of ammonia poisoning include sluggish behavior, panting, and gill discoloration (gill burn). Fish may hang just below the water surface. The easiest way to confirm ammonia poisoning is by testing the water. Ammonia poisoning can be reduced by reducing feedings, making water changes, lowering the pH, using zeolites, and increasing aeration.

Nitrite/Nitrate Poisoning
Nitrite/Nitrate poisoning is caused by the same activities as ammonia poisoning. Nitrite/Nitrate poisoning has the same symptoms as ammonia poisoning, and can be tested by a Nitrite/Nitrate water test kit. The best course of action, is to reduce feeding, make frequent partial water changes until the compounds are reduced, and increase the aeration in the water.


---------- FOLLOW-UP ----------

QUESTION: Thanks!  I am changing the tank now.  Also, when I changed the tank yesterday, I changed about 30 percent of the water and added some aquarium salt.  Then, later I put her on an antibiotic called Furan-2.  Nothing seemed to help.  She was huddled at the bottom of the tank for most of the day yesterday and still is today.  I hope that the tank changing helps.  If you have any other advice please let me know ASAP.  I really appreciate your help.  Thank you!

Answer
Hi

kindly please give her some time to recover , do not add every thing in the same time , the effect will be hard to her infected body which is too sensitive now ,

Just do as advised before , test the water , make frequent partial water changes until the compounds are reduced , and increase the aeration in the water ,  lowering the pH, using zeolites , and for the time being reduce feeding , and you might turn the filtration end away from her to the side or vertical , but do not put any kind of stress into her , she will recover soon ,