One fish always dies, Why?

Question

Okay, we just got a new tank and are kind of new to fish owning. Our water is ok, we got it tested. But every time we get a new batch of fish ( 4 of them this last time, and a sucker fish) they are just regular goldfish+ the sucker fish. We notice that 1 fish stopped eating. He kind of swam around the top of the tank with his 'nose' sticking out of the water. He would swim to the flakes at the top and bump into them but wouldn't eat them. The other fish are fine and happy. The sick fish would swim to the bottom and socialize with the others for a little while then float back to the top. after 3 days, it finally died. Is there anything we can give to a 'sick' fish to avoid this? they are my 5 year old sisters fish and she seems to be getting discouraged that her fishies keep dying. and no she doesn't do anything to the fish, she's very careful about them. It is a 20 gallon tank, has 1 live plant, several plastic ones, natural rocks, a sunken ship with bubbles and a filter

I don't think you people are talking about my goldfish, my goldfish are only about 1 inch long, and my sucker is only 2 or 3 inches long. the sucker is the other type, not the chinese alge eater or something like that. I get my fish at Petsmart, we don't go to wal-mart cause half the fish in the tanks are dead anyway. It wasn't the sucker that was sick, the goldfish that was sick is already dead. We plan on getting a bigger tank when the sucker fish gets bigger. I don't think the sucker is doing anything to the fish because he hides in the boat all day.

we let the tank run for 2 days before we added the fish, then we went and got the fish, and let them sit in the bags in the water for 30 minutes then took them out of the bag and put them in the tank.

Answer 1

Your tank is experiencing 'new tank syndrome', which is basically ammonia and nitrite poisoning due to the absence of sufficient beneficial bacteria colonies which process those toxic compounds into less harmful nitrate. Basically your tank isn't cycled. Which most of the previous posters have indicated. Get your water tested (ammonia and nitrite should consistently undetectable when the water is tested).

Fish should never be added into an uncycled tank unless they're extremely hardy or casualties will occur.

Additionally (since you're new and just starting out), fish tanks are stocked based on the maximum adult size of the fish and other factors, not size at purchase. Remember, your goldfish (if they survive) won't stay small forever, and are considered substantial waste producers (which is why your tank is considered overstocked).

Answer 2

your tank is overcrowded. Even tiny feeder goldfish need at least 10 gallons each untill they reach about 5 inches in length then they need 20-50 gallons each. You can probably fit 2 fancy (fat bodied)goldfish in the 20 gallon tank (fantail, oranda, moors etc) comets or slim bodied goldfish are pond fish & really should not be kept in tanks. So yes we are talking about YOUR goldfish... all goldfish actually... The tank is not cycled, so the ammonia & nitrite are not being broken down fast enough, and are reaching toxic levels. Start with one fancy goldfish untill your tank is cycled then you can add another (it takes between 4-6 weeks) do 25% weekly water changes off of the top of the tank for those first 6 weeks and do not change the filter cartridge, then after your tank is cycled, add a friend, and be sure to siphon the gravel every 2 weeks and do a 25-50% water change every 2 weeks. Don't forget to treat the water with a conditioner that removes chlorine, chloramines & toxic heavy metals. Do not use amaquell or any other ammonia fixing chemical, as this will prevent your tank from actually cycling. feed lightly once a day (about what the fish can eat in 1-3 minutes) net out any remaining food. Dont get a sucker fish, they only eat algea when they are babies and will eventually attack the goldfish. For algae controll try malaysian trumpet snails, or just get a algae scrubber to clean the sides of your tank.

Answer 3

First off, how long has it been running? Where are you buying your fish? Most fish purchased at Walmart don't survive. If this is where you are buying them, change stores.

If the other fish are healthy or seem healthy (gold fish) These are cold water fish. What kind of sucker fish do you have?

If your tank is not cycled properly, the ammonia spikes can be killing your suckers. Gold fish are hearty and can withstand some of these spikes with little to no effect (unless it is really bad)

Here is a link to understanding cycling:

http://freshaquarium.about.com/cs/biologicalcycle/a/nitrogencycle.htm

Sounds like ammonia spikes to me since sucker fish are more of the bottom strada fish. He is going to the top of the tank since ththat is where the ammonia will be less in terms of parts per million.

Have YOU tested your tank water or did you take it to the store? Honestly when you are testing your tank water, you should take water from the middle to bottom layer of your tank. This will give you a more accurate reading on ammonia and nitrates. Use a clean turkey baster to gather the water.

you can do a 25% water change to help with the ammonia.

Answer 4

Unfortunately I don't know what to tell you about what happened with the "sick" fish, but your tank is way overcrowded if you aren't planning on upgrading soon. You need at least 20 gallons for EACH goldfish. They grow to be around 8 to 12 inches long. It may upset her, but you need to take some of them back to the pet store. Also, about your sucker fish, what kind did you get? Is it a plecostomus or a Chinese Algae eater? Chinese algae eaters get very aggressive with slower moving fish, which goldies are, and will start to attach themselves to the fish and eventually will kill it. A pleco is a better idea, but these also grow quite large, a good 6 inches for the smaller types. It seems you need to take back some fish or get a MUCH larger tank. Good luck!

Answer 5

your 20 gallon tank is really only big enough for two goldfish, you have two many fish in your tank, plus your sucking fish will also grow, they fight sometimes until they feel comfortably in the tank, the weak ones will die first, they produce a lot of waste, and your water will get dirty very quick, also try only to feed what they can eat in two minutes, dont over feed as that can also be bad for them, are you putting water softner in when you change your water, rem only change 25% once a week, hope this helps, x

Answer 6

my sister had a fish tankshe started with about 12 gold fish and now she only has 3 left
my mom said she thinks that they get in a fight and eat each other
i dont know if thats right or not but it might help some