So, I set up a 55 gallon for a local school with zebra danios. mollies, guppies, kuhilli loaches, cherry shrimp, and neon blue gourami's, the other day the teacher told me that the shrimp were dying. I had them test the water with a master test kit and they reported to following, 0 ppm Ammonia, 0 ppm Nitrite, and 0 ppm nitrate. this shocked me as i know that they have been topping the tank off and rarely doing actual water changes so i asked them to test it again expecting to see nitrates. They retested and sent me a picture of the test and still got 0 across the board, at this point I went down to the school with a new master test kit and tested the parameters and got the same thing twice and got a ph of 8.6. is it possible that without plants something in the tank is eating nitrates? Also, there is a large piece of driftwood in the tank so i expected a lower Ph reading any ideas on what's going on with that?
NO Nitrates
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10g: 8 young golden Dalmatian mollies 1 neon tetra 2 nerite snails 10g: 2 nerites, soon molies fr t1
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No nitrates is unusually ok. No idea what is causing it tho
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Is there a lot of debry? Hazy/turbid water? Lot of brown gunk in the filter?
No nitrates may be possible if your bacteria are mostly heterotrophic. The tank inhabitants would be more prone to disease which would also explain the shrimp dying.
No nitrates may be possible if your bacteria are mostly heterotrophic. The tank inhabitants would be more prone to disease which would also explain the shrimp dying.
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I’m gonna suggest that both test kits are faulty. If it was a liquid test kit the reagent #2 bottle needs to be banged against something solid as well as shaken.
Wood will only reduce the pH in very soft water. At a pH of 8.6 it’s unlikely to be soft.
Is the filter media porous? If so it’s possible that it contains anaerobic bacteria that are consuming the nitrates.
Wood will only reduce the pH in very soft water. At a pH of 8.6 it’s unlikely to be soft.
Is the filter media porous? If so it’s possible that it contains anaerobic bacteria that are consuming the nitrates.
Heterotrophic bacteria produce ammonia so there would still be nitrates. Also the tank inhabitants would not be more prone to disease if there are no nitrates. They would be less prone to disease. Nitrates are a stressor and the ideal level for shrimp and fish is zero.
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I mean this anabolic pathway:
Assimilatory nitrate reduction, a form of anabolism, incorporates nitrogen from nitrate into the organism’s biomass.
Reference: Nitrate and periplasmic nitrate reductases
While I agree that the lower nitrate level the better it is for aquatic fauna, I was suggesting that pathogenic microorganisms may be responsible for both the death of shrimp and for assimilatory nitrite reduction.
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If you're using the API master test kit, you really have to shake that second nitrate test bottle. Vigorously for two minutes or more. And then you have to shake the test tube hard for one minute. Otherwise, you might not get accurate test results.
I recently tested again and got a ph. of 8.2 and 10 ppm nitrates I tested the source water and got ph7.4 before and after degassing the source water with no ammonia nitrites and nitrates. I am still not sure what is happening to the nitrates as they should be much higher with the stocking levels and the timing of water changes on this tank. But it is working so I am not going to fuss too much over it. it is filtered by a pair of sponge filters each sized for a 120 gallon tank.
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