Urgent, Please respond. Sick Goldfish

Question
QUESTION: Dear Jaymie
My roomie recently purchased a goldfish named Oscar. He resides in a 3 gallon aquarium that has a bubble filtration system. Today we cleaned out his tank and tried using tap water instead of distilled water. We added 6 or 7 drops of Nov Aqua Water Conditioner and kept him in a bag submerged in the new tap water so he could get used to the temperature. After 1 1/2 hours we took him out and let him swim.  He was fine for a few hours but now he's lying at the bottom of the tank and thin clear strings appear to be coming out of his gills. He's still breathing but won't respond to our taping on the side of the tank. Please, is there anything we can do to help our fish? Thank you so much
Sincerely,
Megan

ANSWER: Megan,


Firstly, your tank is too small. Goldfish need 20 gallons minimum per fish. Never completely clean a cycled tank that has a filter. You only need to change 25 % of the water every week. If you remove all of the water during your cleaning, you are cycling the tank again. Don't use distilled water at any time. Always use your tap water. When add new water to the existing water in the tank, make sure it is the same temperature. Always adjust the water going in never wait for the water to be the same temp. When doing the water changes, never remove the fish. Leave him in the tank. If you need to remove the fish, take water from the tank and put it in another tank or large bowl and then put your fish in. Never, put your fish in a bag.

Now for the real problem. Is your fish scratching against surfaces, redness of skin, mucus on the gills or body, sunken bellies and rapid breathing. Mucus on the gills can keep it from opening? I need to know as much as possible in order to help you out and save your fish. I will continue to check on here to see if you have come back to me with what he is doing exactly. Hopefully then I can help you figure out the best way to treat him. What are your water readings? What are you feeding him?

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

QUESTION: Dear Jaymie,
Unfortunately, Oscar the Goldfish passed away. He was breathing rapidly and it could be that the thin fibers extending from his gills were mucus. He is sorely missed. But what you have told me helps a lot in case we decide try again with a new fish. I have several bettas in seperate tanks. Do the same rules apply to them as to the goldfish? Is five gallons enough for one male betta?
Thanks so much!
Megan  

Answer
Megan,

Sorry to hear Oscar didn't make it. Yes 5 gallons is perfect for 1 male Betta. They are a lot different than goldfish. Betta's need a heater set no colder than 82 degrees. Since you have Betta's, a liquid water tester is a must. As far as water changes go, yes they are the same. Make sure the new water is at the same temp as the tank or your Betta will go into shock. With Betta's pick one day where you don't feed them. You can even feed them 1 pea a week but not necessary. This will help prevent swim bladder disease. Make sure there is nothing in the tank that can catch a fin or tail, but other than that they are awesome fish. I have 11 adults and 2 tanks of fry. Make sure you have a Betta water conditioner that removes ammonia, nitrates, and nitrites from your tap water. If you can find it, i would suggest buy Black Water Extract to put in their tank. It is an awesome product. Your Betta's color will be sharper, they will be more active, and with my males, I have to remove huge bubble nests to feed them every day.