Fish are gasping for air.?

Question

I have two oscars, one about 6 inches and the other about 5, and two plecos, about 5 inches each. I have had them for a long time now. I recently changed filters from a hanging filter (whisper) to a Fluval 204 (30 Gal tank). I changed about 60% of the water, cleaned the rocks, the works. well, now my oscars are gasping at the top of the tank, they don't move much and don't want to eat. I am worried. I like my fish and have had them to long to lose them over something that i did wrong.

help.

Answer 1

sounds like ammonia poisoning or lack of oxygen. bascilly you cleaned ro replaced everything right. there a good chance that you dont have enough bacteria to handle biological filtration. you might have a lack of oxygen due to that as well or a slower filter, i think that plecos can take in oxygen through there intestines and the fact that only the oscars are gaspping makes me think O2 depletion. i would add a bacteral additive and amquel+ for ammonia control i dont like adding chemiclas but i might help. also add an air stone for more O2, a powerhead maybe but if im not mistaken most amazon fish dont prefer alot of current. test for ammonia and do some more water changes to keep it down evry few days

fluvals have a return line under the water where your whisper disrupted the surface to add more oxygen

Answer 2

With hanging filters when the water falls it puts oxygen in the water. Fluvals (depending how submerged you have it) don't create as much disturbance therefore less oxygen in the water. It might help to move the Fluval where the outake will disturb the water more (near the surface).
The easiest solution for you might be to add an aerator and see if they breath easier.

By changing your filter and cleaning everything else in the tank your tank will probably be re-cycling itself. They may be suffering from an ammonia spike like others said. It could help to do some small 15-25% water changes to keep the ammonia level down.

(Also, changing 60% of the water isn't nesessary. A 25-50% max would suffice. I'd also consider upgrading those fishies to a bigger tank, especially if you have the type of plecos that get huge)

Answer 3

Classic ammonia poisoning from the sounds of it. That's a lot of fish for the size of the tank (and you'll need larger eventually for the oscars alone). But when you cleaned the gravel and changed the filter, you probably cleaned a little too well, and now the bacteria that are the biological filter are reduced. Do a 25-50% water change asap, and if you have a test kit, test the water tomorrow to see if you need another (ammonia and nitrite should both be under 0.5). Until you reestablish the bacteria, you'll need do be doing more frequent water changes.

http://freshaquarium.about.com/cs/disease/p/ammoniapoison.htm
http://freshaquarium.about.com/cs/disease/p/ammoniapoison.htm

Answer 4

id go with pyros answer ive been keeping and breeding fish for years and thats about the same answer id give that 60% water change and a new filter without bacteria was a pretty big shock to the tank an fish check ammonia cuz im sure u had a ammonia spike in there in few days and a couple 25%water changes should help it out in other words its just as if u sat a new tank up an through the fish in right after

Answer 5

Changing that much of the water AND replacing the entire filter unit at the same time wiped out all the nitrifying bacteria you had in the tank. Your oscars are suffering from ammonia poisoning. Go to the pet store and pick up a bacteria culture, like Cycle. This will replace that bacteria and help it start to thrive again. For future reference, never change more than 1/3 of the water at a time, and never change the water and your entire filtration system at the same time. it wipes out too much bacteria, causing the ammonia spike you're seeing now.

Hope this helps.

Answer 6

Good advice here but you might also want to check with a local aquarium fish dealer and see if he has some ideas to offer. Also, you can take a water sample in and have it checked for chloromines, pH, nitrogen levels, etc. While it sounds like oxygen starvation it could be something else. Usually people who sell fish are eager to help solve your problems because that would make you a potential customer.

Answer 7

meaning your aquarium does not have any/little or no dissolved oxygen left interior the tank. The fish is in simple terms attempting to get one final breath of unpolluted air, yet interior the top they have been given too drained and died of suffocation. attempt to place in air pumps and aerate the aquarium, to maintain the water shifting and not stagnant. Your fish would be happier that way. yet another tip is which you may desire to to maintain a special interest to the water temperature besides. some fish prospers extra suitable in heat water, and a few can breed extra suitable in cool water based on the species. happy fish-keeping :)

Answer 8

Maybe the new filter isn't working properly, you should check it out
Otherwise I would just put the same kind of filter back in there you had before, maybe they don't like the new one

good luck

Answer 9

60% water change and a new filter will impact them..make sure your temp isnt too high as hotter water carries less oxygen. also do you have your bubbler on? and when you did the water change did you use a water conditioner? i would assume it was the difference between the water they had, and the water you added was a drastic change(warmer water, colder water,ph was much higher/lower) all kinds of things can impact them.

Answer 10

check the filter...are you sure its working and the outlet is working? its sounds like an ammonia problem you need to do a water change right away