If a tank has had no fish in it for a month, does it have viable bacteria or must the cycle start all over fromthe beginning?
This question comes up from time to time and so before I clean out this tank, I figured I'd do a quick experiment.
The fish in the 58 gallon tank were sold on Nov 21, today is Dec 23. The tank has been running with no water changes or filter cleaning since the fish left. Dual Canister filters are running, water temp at 72, gravel is pretty clean as the tank was recently moved and totally cleaned then and gravel was kept very clean after that. It also has some Tx holey rocks and plastic plants. For while there was one tiny live anubias plant on a rock but I removed it a week ago. It is possible that there was enough decay of plant parts that some bacteria may still be alive in the tank.
Although I did an initital ammonia test, I forgot it takes 5 minutes to read, so I cannot be certain the tank was ammonia free to begin with, but let's assume it was. I have dosed it to ~3.0 ppm ammonia with 20 ml of household ammonia to a 58 gallon tank.
I'll retest tomorrow at about 2 pm (hopefully, being Christmas I may get distracted) to see how the ammonia has dropped, if it has dropped. I suspect that the bacteria will rapidly spring back into action. If the ammonia is down substantially in 24 hours, we'll know.
This question comes up from time to time and so before I clean out this tank, I figured I'd do a quick experiment.
The fish in the 58 gallon tank were sold on Nov 21, today is Dec 23. The tank has been running with no water changes or filter cleaning since the fish left. Dual Canister filters are running, water temp at 72, gravel is pretty clean as the tank was recently moved and totally cleaned then and gravel was kept very clean after that. It also has some Tx holey rocks and plastic plants. For while there was one tiny live anubias plant on a rock but I removed it a week ago. It is possible that there was enough decay of plant parts that some bacteria may still be alive in the tank.
Although I did an initital ammonia test, I forgot it takes 5 minutes to read, so I cannot be certain the tank was ammonia free to begin with, but let's assume it was. I have dosed it to ~3.0 ppm ammonia with 20 ml of household ammonia to a 58 gallon tank.
I'll retest tomorrow at about 2 pm (hopefully, being Christmas I may get distracted) to see how the ammonia has dropped, if it has dropped. I suspect that the bacteria will rapidly spring back into action. If the ammonia is down substantially in 24 hours, we'll know.
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