I bought a 10gal aquarium about 6 months ago I had bought 4 glow fish and 2 neon tetra and the black light for the glow fish. The glow fish would hide under the filters and then after about 1 week they started dying I tested the water with the test strips and it was fine I went to petsmart with a water sample they said it was fine and replaced the fish about a week later it happened again so I got different fish 2 none tetra 2 red lid tetra and then petsmart sold be a bunch of chemicals for the tank I have done complete water changes bought new gravel and my fish keep dying please help
Freshwater Aquarium Gravel : What You Should Know | Home Aquaria
For the first day after the change, cut back on the amount of food you feed the fish. Also, darken the room near the tank to reduce their stress. You should check the ammonia levels in the tank about three days after the gravel change. Check again in three days, and check a week after that. If at any time the ammonia levels are high, change the water and test the ammonia frequently until it is cleared out.
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What uneaten food and fish poop that isn’t removed by your filter settles into the gravel and is then set upon by the nitrifying bacteria thereby converting it into nitrite. By disturbing the gravel you probably found your water became rather dirty to look at. Left alone it would have cleared in an hour or so, time dependent on the effectiveness of your mechanical filter. Remember also that the gravel forms part of your biological filter, so by disturbing it….well you can guess the outcome.
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