***irrisdecent fresh water shark SICK****

Question
*******Dear Chris, Very worried. My shark is almost a foot long. I've had him for 3? years. I did a 3/4 change today (which is more than I usually do). I did this because my shark was having a hard time stay at the top of the water as he always does. He is not swimming back and forth and goes to the top to get air. The 2 plecos (one is 1 foot long, the other is 7 inches) they are not black-ish as usual they are turning a grayish white...and listless.The ammonia and nitrates test perfect. I added some salt. In the tank are a parrot fish about the size of a woman's fist. Also,  2 plecos, 1 big, 1 medium. Plecos seem to have lost energy also. I need help please. I love my shark and am frantic. He is part of the family.****** 1. tank set up for 4 years. 2. tank is 65 gallons.. 3. type: above    4. typically i change water 1/3 about every month. They have always responded well to this.
FILTER: pro tech. I just put in new carbon filters tonite also. PLEASE  HELP I AM SO WORRIED. MY SHARK IS THE BEST ENJOYMENT of any fish I've ever had. If I lose him I lose years of loving him.........................Pam

Answer
Hi Pam;

He may have a swim bladder problem. The swim bladder controls buoyancy. There are many causes for the swim bladder to fail; Shock, constipation, infection, waste toxin poisoning, injury, cancerous tumor, etc. If he he is still eating, offer cooked peeled green peas for 3 days and no other foods. They have a laxative effect. If he isn't feeling better after a couple of days you could try an antibiotic food. There are some available at many fish stores. Medicine added to the water isn't going to have any effect because he is so big. It only works in smaller fish.

If the plecos were okay until the water change was made, they may simply be in shock from it and the shark does indeed have some physical problem of his own. 75% is a big change in one day and can easily cause fish to be very stressed.

If they were all acting strange before the water change, it could be a water quality problem. You have some very large fish in there and their waste load on the system may just be too much if they have grown since you first put them in there. All tanks need a 25% water change once a week, every week with gravel vacuuming to have healthy fish. This is especially important with big messy guys like yours.

I noticed you tested the ammonia and nitrate (NO3), but the nitrite (NO2) level needs to be tested too. It can cause the fish to act just as they have been. Test for it as soon as you can and do another water change in the meantime. Avoid changing more than 25% at a time though. It can cause shock. If the nitrites are indeed elevated, keep making daily 25% water changes. Nitrite poisoning causes a condition known as "brown blood syndrome". It alters the fishes' blood so it cannot carry oxygen as it should. Aquarium salt helps to counteract this effect. Add an initial dose of 1 teaspoon of salt per gallon. Add more at every water change, but only for the new water. For instance, if you replace 10 gallons of new water, add 10 teaspoons of salt to treat the new water. Add more air bubbles to the tank too. It will help raise the oxygen levels. Once the crisis is over, stop adding salt and your regular weekly 25% changes will slowly remove it.

There is a possibility they are all infected with a parasite or bacterial infection. Look for spots, dots, redness, etc. Let me know if you find any other symptoms.

At Your Service;
Chris Robbins