Water Changes

[jrussuk]

hi
ive done my 1st water change and after 24 hours i notice my nitrites has gone up slightly .03pmm i have a ten gallon tank with 5 microrasboras in it plus some plants ive tested my tap water and no nitrites are showing also tested my tank for ammonia and read 0. the tank was fully fishless cycled and the fish look and act fine. is this normal
many thanks

 

[WILDER]

Did you do a gravel vac as well and how much.
Sounds like you overdid the water change how much did you remove.

 

[Bignose]

Is is 0.3 ppm or 0.03 ppm? I ask since 0.03 ppm is virtually undetectable by home test equipment, but 0.3 ppm is a significnat problem. Anyway, nitrite after a water change is not normal, keep testing, the tank may not have been as cycled as you thought it was.

So long as you match water temp, hardness, and pH, contrary to what Wilder may think, I believe that there is no such thing as over-doing a water change. In fact, if your nitrites keep rising, I'd be ready to do several large waterchanges as needed to dilute the concentration of pollutants. I am talking as much as 75% if the ammonia or nitrite concentrations got too high. Again match water temp, hardness, and pH, and you should be fine.

So, test every day, and if the nirtrites keep going up, I'd be prepared to do large water changes. If the tests read 0 for several days running, I'd just chalk it up to a random event and not worry about it.

 

[mnbyiuopre]

Is is 0.3 ppm or 0.03 ppm? I ask since 0.03 ppm is virtually undetectable by home test equipment, but 0.3 ppm is a significnat problem. Anyway, nitrite after a water change is not normal, keep testing, the tank may not have been as cycled as you thought it was.

So long as you match water temp, hardness, and pH, contrary to what Wilder may think, I believe that there is no such thing as over-doing a water change. In fact, if your nitrites keep rising, I'd be ready to do several large waterchanges as needed to dilute the concentration of pollutants. I am talking as much as 75% if the ammonia or nitrite concentrations got too high. Again match water temp, hardness, and pH, and you should be fine.

So, test every day, and if the nirtrites keep going up, I'd be prepared to do large water changes. If the tests read 0 for several days running, I'd just chalk it up to a random event and not worry about it.

If the tank isn't fully cycled though a 75% water change could cause even more damage by removing beneficial bacteria. That is only if the tank isn't fully cycled like WIlder suggested.

 

[Majjie]

If the tank isn't fully cycled though a 75% water change could cause even more damage by removing beneficial bacteria. That is only if the tank isn't fully cycled like WIlder suggested.

No - it couldn't. The bacteria don't live in the water - they adhere to solid surfaces. Very large water changes won't do any harm - as long as the water is fairly well matched in temperature and chemical composition (as Bignose says)

 

[Bignose]

mnb, Majjie has the facts exactly correct. The fancy word describing the bacteria is sessile, which is the opposite of mobile. That means the bacteria adhere to the surfaces and very, very, very rarely do they detach and swim around. It is like 99.99% of the bacteria are on surfaces, not mobile in the water. And so long as you refill the tank pretty quickly, so that the surfaces do not dry out, the bacteria will be fine.

In addition, the cycling process is a dynamic equilibrium where the exact amount of pollution in the water does not matter. Cycling is a balancing of rates; when the rate of ammonia production and the rate of ammonia consumption are balanced, then the tank is cycled. The rate of ammonia production is a dependent upon how many and what fish are in the tank, not on the snapshot reading you get when you take a reading. That is, regarding ammonia production, it does not matter if there is a 1 ppm reading, or you do a 75% waterchange and reduce that to 25%. Over the next hour, the fish are going to produce the exact same amount of ammonia. That is why the tank is cycled when the rate of production and the rate of consumption are balanced. And also why you can, and for the sake of the fish's health, you should do water changes while cycling. It will not slow down the cycling process, and it will keep your fish from being exposed to the pollution.

I read a paper recently, and I can hunt it back out for you if you want, that showed that fish that are exposed to high concentrations of ammonia have significantly higher rates of health problems for the remainder of their lives. In other words, exposure to high concentrations of ammonia can lead to lifelong weaker immune systems for the fish. That is why I think it is critical to do large water changes if a mini-cycle should occur, or if you choose to cycle with fish.

 

[jrussuk]

sorry couldnt get back to everyone yes i done a small gravel vac and changed bout 20% of the water tested water this morning and nitrites are down to 0 again