My sister has a comet goldfish in a 23 gallon tank. (I know how terrible this is, please don't tell me.) He hadn't had his water changed for 6 weeks. (Also terrible). At the 4 week mark, I dropped some Safe (the same as Prime, but more concentrated) into the tank.
The pH is 6. The water is extremely soft. I know this is bad too.
After the 6 weeks, the readings were:
How is this possible? How were the readings so low? I was dreading finding something like ammonia: 8 and nitrates: 4 billion and 2.
Depending on the size and age of the goldfish, filter capacity, live plants, how much it gets fed, the decaying waste matter, how old/established the tank is, and if it's cycled or not, the levels aren't very common yet they aren't unheard if eithe. I would say that the tank is cycled and the goldfish is emitting low amounts of ammonia, unless you have live plants as presumably the nitrates would be higher without them
The amount of nitrifying bacteria mainly depends on one thing, other than the amount of oxygen, light, etc. mostly food. As in ammonia. The amount of nitrosifyers can very greatly depending on the amount of food, in this case ammonia present. Nitrosifyers, such as nitrosococcus, And nitrosomonas. (there are more types of nitrosifyers but these are the only in an FW system) will convert toxic substances such as ammonia into equally toxic ones, in this particular situation, it would be nitrites, nitrites then get converted into less harmful substances by nitrifying bacteria. By nItrobacter (there are more types of nitrosifyers but these are the only in an FW system) the result of this would be nitrates. So the amount of nitrates you have can represent the amount of ammonia being produced. With live plants this process of destination can be puzzled greatly. So from the low levels and no water changes or replacing water that has evaporated I would predict that the goldfish is very small.
Sorry, I should have mentioned...the goldfish is ten inches long. The tank is bare bottom, no live plants. It is cycled (and thanks, I do know how the cycle works, but your explanation was great :)). He is overfed, in my opinion. He should be emitting more ammonia than all of my fish together.
Hmmm. I'm puzzled is it an open topped tank? Does she refill it if it is? My dad has a fairly overtired ten gallon, cycled with no "watr changes" but it's an open topped tank so he has to replace about 40% of the water weekly
No, the API test is for NH3/NH4+ together. What I'm saying is that the ammonium is being consumed at a steady rate (though the .2 indicates that there is perhaps not enough surface area to handle all of it).
I can't find much info on the nitrate thing. Oddly enough, searching it turns up with mostly goldfish related questions. xD
The only thing I can think of is if you're doing the nitrate test properly, or if your filter contains nitrate absorbing medium. Posted via Mobile Device