Water Changes...Unnecessary?

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Love this debate, however when arguing for the lethal and/or safe maximums u must remember that tempeture of water(which also effects oxygen etc), age,acclimation , species and strains/catch locations, and many other variables will effect the fishes tolerance .
 
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The other guy is making some pretty wild speculations,assuming that all aquarium fish are hardier than trout for example.

The studies on rainbow trout are inconclusive. They report nitrite levels alongside nitrate....
I know RD. isn't a fan of Diana Walstad, but it is exactly what she said many years ago in her book. There are no decent nitrate studies that also don't involve some sort of elevated nitrite level. The case is still the same in all high nitrate studies I randomly open and read from start to finish.... The water they're keeping the fish in also have elevated nitrite.....It's like punching your chest with a broken finger and thinking the pain is coming out from your chest....

A more decent study would involve sensitive aquarium fish, kept in aquarium settings long term, with nitrate levels coming from fish pollution.....I've done an annecdotal one myself...I just simply stopped doing water changes for 5-6 months on a heavily planted tank. Nitrate levels were below 5ppm, the colour was just barely turning on my test. TDS levels were through the roof, double my tap water, and some of my fish got sick, which ended the experiment.....You can control nitrates with plants or other means, but the pollution and disease comes from something else.....I personally don't care at all what my nitrate levels are....I am a proponent of TDS/conductivity meters as a measure of pollution...and I consider large regular water changes essential.
 
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Salmonids are among the most sensitive of all species studied. Find me a tropical fish that tops them in nitrate sensitivity then find a bunch more. Hint: guppies were studied.
That doesn't mean that they are most sensitive to most things, you have to remember that most aquarium fish have not been tested at all.
 
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A more decent study would involve sensitive aquarium fish, kept in aquarium settings long term, with nitrate levels coming from fish pollution.....I've done an annecdotal one myself...I just simply stopped doing water changes for 5-6 months on a heavily planted tank. Nitrate levels were below 5ppm, the colour was just barely turning on my test. TDS levels were through the roof, double my tap water, and some of my fish got sick, which ended the experiment.....You can control nitrates with plants or other means, but the pollution and disease comes from something else.....I personally don't care at all what my nitrate levels are....I am a proponent of TDS/conductivity meters as a measure of pollution...and I consider large regular water changes essential.

I reached 95 mg/L NO3-N before my last water change. TDS was well over 500 ppm. Fish were fine and are still fine.
 
That doesn't mean that they are most sensitive to most things, you have to remember that most aquarium fish have not been tested at all.

If all tropical fish were studied, a few species would probably come close to salmonids in nitrate sensitivity but the majority would be a lot more tolerant.

Let's make a list:

Tropical fish more nitrate-tolerant than salmonids:

guppies
tilapia

Tropical fish less nitrate-tolerant than salmonids:

[Feel free to add here]
 
If all tropical fish were studied, a few species would probably come close to salmonids in nitrate sensitivity but the majority would be a lot more tolerant.

Let's make a list:

Tropical fish more nitrate-tolerant than salmonids:

guppies
tilapia

Tropical fish less nitrate-tolerant than salmonids:

[Feel free to add here]
Your asking a question with no known answers, yet your speculation is as overinflated as your pride and arrogance, in the end you are playing Russian rullete with the truth, assuming there are no bullets in the gun without checking to see.
 
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