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My fish need oxygen!!! Why?

August 17th, 2006, 06:58 AM
Hi my room-mates aquarium has been doing great for the last 2 years or so. The fish have all done well, and since the initial learning, we now know the best fish to have in the tank. But today, all of the fish are going to the top of the water, like they are going up for air. Why would this be? She cleaned it this weekend, like she always does and she has never had a problem before. Everything seems to be working fine...
Anybody have any ideas???
We have turned down the temp a little, and stirred the water, to increase oxygen, but those are just short term fixes. What is causing this to happen???

August 17th, 2006, 07:32 AM
Ok, I just read somewhere that itmay be due to nitrite poisoning. It said that to treat it you can add salt. How much salt would you add? Somewhere I read 1 tsp per 300 gallons, and somewhere else said 1 tb.sp per 5 gallons. So I don't want to add anything until I know for sure...

August 17th, 2006, 10:39 AM
I just went to the pet store during my lunch break and got something to add to the filter to take out the toxic ammonia and nitrites. Hopefully this will help. In the meantime, I am going to bring them a sample of the aquarium water to make sure that that is what the problem is.

August 17th, 2006, 06:26 PM
fresh water or salt?.........not that it really matters that much........stay on top of the ph level ..........the level varies for different fish types....

August 17th, 2006, 09:10 PM
It is a freshwater tank. A tetra has died already, and two other fish don't look too good...I added that nitrite remover to the filter, hoping that it will make a difference. Tomorrow I will drop off a sample of water to the pet store to see if they can tell me if what I am doing is right. But I felt I had to do something in a hurry...and when I explained what the fish were doing, and after doing some reading, I really think that it is high nitrite level...Hopefully I won't wake up tomorrow to find all the fish dead. :confused:

August 17th, 2006, 09:52 PM
Possibly the biological filter crashed on you. Do a water change (50%) everyday for a little while... get a nitrite test kit... your bacteria needs to colonize (tank needs to cycle) if that is the problem.

Most things can be fixed with frequent water changes... If it is lack of Oxygen (but I don't think it is) you could add a bubbler.

August 18th, 2006, 01:35 AM
Hi there,
often fish will go to the top for extra oxygen when there is an
ammonia spike in the tank. Salt wont do anything for nitrItes or ammonia.
I suggest that you purchase test kits for ammonia, nitrItes and nitrAtes,
to help monitor the situation.
Have your ph tested too....and add some peat moss to the filter,
this will lower the ph, and make the water more acidic, which will
in turn reduce the harmful effects of ammonia and nitrItes.

Do you use Prime water conditioner? If so, drop in a full dose of it,
for the gallons of the tank, and it will detoxify ammonia and nitrItes.
Also, consider adding an air stone, that could help as well.

How often do you do water changes?
I highly recommend at least 35% once weekly, vaccuuming 50%
of the gravel each time, alternating sides.

Also, did you change the filter cartridge at the same time as the water change? This can cause a loss of biological bacteria, and can cause an ammonia spike and a mini cycle.
Always stagger water changes and media changes....always one week between each.

August 18th, 2006, 01:23 PM
I brought the water to the pet store to be tested, and the pH was found to be a little high. The girl at the store said that a combo of pH and nitrites may have made them gasp at the surface, so to continue with the nitrozorb that I bought. In the meantime, an angel fish died last night, along with the tetra and a bottom feeder yesterday. But today all the rest of the fish seem to be back to normal. Monday I am going to bring another sample of water to see if anything has changed. Hopefully the worst is over.

August 18th, 2006, 06:27 PM
Hi there,
If the tank is Cycled there should be no Nitrites - tests should come
back 0.
Do you know about the Nitrogen Cycle?
Its when the ammonia created by fish waste in the water is
transformed by nitrobacter bacteria into first NitrItes, then NitrAtes.
A fully cycled tank, which is safe for fish, will give you test results of 0
ammonia, 0 nitrItes, and 5 or more ppm nitrAtes. If Ammonia or NitrItes are present, the tank is not safe for fish, and fish will die because of NitrItes
I highly recommend to you to get the product Prime...its a water conditioner that removes chlorine and chloramines (which can be fatal to fish), and it detoxifies ammonia, nitrItes, and nitrAtes, so can help fish survive in a cycling tank.

It sounds to me like either the tank is new and is still cycling, or something has been done to cause the cycle to crash.

For a cycle to crash, there is a few things that can be mistakenly done to cause this, the most common of which is Changing a Filter cartridge at the same time as doing a water change. The good bacteria lives in the filter cartridge and the gravel of the tank. If you clean the gravel you remove some bacteria, and if you replace the filter cartridge at the same time, you essentially are removing 90% or more of your good bacteria.
This will cause a tank to crash and a mini cycle to happen, where you will lose fish to ammonia/nitrItes poisoning, which is by the way a super painful harsh death for the fish.

Another thing that cause tank crash is over population and over feeding.

What size is the tank and what fish were in it?
IDeally, to prevent overstocking problems, you should limit yourself to approximately 1 inch of adult fish per gallon. So, an Angelfish is 10 inches at maturity, so would take up 10 inches of stocking, for example.
Also, Angelfish can grow to be 12-16 inches tall, and need a tank at least 18 inches tall, of which the smallest size made in this height is 29 gallons.

I strongly feel that before you continue on with the tank you should try to figure out what caused this problem.
Fish dont just drop dead suddenly.

August 20th, 2006, 05:20 PM
Thanks SneakyPete for your suggestions,

I will definetely look for the product Prime that you recommended. I havent' heard of it before, but it sounds like it will help.

I think that the cycle crashed, like you had figured.

The filter and the gravel cleaned about the same time, so I guess that that's what happened.

I know that something happened to cause the fish to die. But I knew that there was something happening before the fish died, as they were gasping at the surface. But by the time I took action, it was too late for a few of them.

Again, thanks for your suggestions, you are very helpful.

August 20th, 2006, 05:39 PM
Wow, you guys make fish-keeping look so difficult. No wonder my fishies always died really quickly.:o

August 20th, 2006, 05:54 PM
Yeah Prin, I agree. It is only within the last 6 months or so that I have any knowledge. I thought that having a fish tank would eb so easy, and as long as fish would get along then you could get whatever fish. But now I realize that certain fish need a lot of water, and all about the ammonia cycle, and that good bacteria are needed, etc etc. Having a fully functional fish tank is a lot of work. :)

August 20th, 2006, 06:00 PM
It must be rewarding though, when you get it right.:)

August 20th, 2006, 07:27 PM
It is amazing. I find the aquatic plants really interesting too. You can keep fish alive pretty easily for a short time, but if you're trying to give them a good life, it can be very challenging! I am really enjoying my new hobby.

August 22nd, 2006, 02:26 PM
Fish keeping really isnt too challenging, so long as you
know 2 things - the tank needs to complete the nitrogen cycle
before its safe for fish, and fish need regular water changes to maintain
proper health.
After that, its pretty easy.
Mix fish by similar temperment, clean the water once weekly 30%,
use live plants to filter out nitrAtes and nutrients from the water,
and make sure all water is conditioned with a dechlorinator and
at the same temp, and its pretty easy.
I have a 10g, 25g, and 75g, and total monthly maintenance is
about 6 hours. Heck of a lot less work than this hamster im babysitting
for my niece.

Did ya know the keeping fish can lower your blood pressure by as much
as 10 points?
Its a relaxing, sublime thing. Give me a tank and some fish and let me
work around in it like a garden, and Im pleased as punch.
Talk about sublimation indeed! :-D

Hunter - just remember not to change water and clean filters at the same time, and your tank should stabilize again in a couple weeks, at which point you will be safe to add fish again - just 3-5 small fish at a time.
Good luck.