Odor in a system

What typically is the cause of odor in a system when water quality parameters such as ammonia and nitrites are fine? Is odor an impending indication of anything? I'm experiencing this in a tank newly stocked with fish that has completely cycled before I added the fish. I'm doing some significant water changes now to see if I can bring the odor down. I may have overfed a little in my zeal to get the fish feeding.

I may have overfed a little

Typically, that is the cause. We're all guilty!

Carbon will usually eliminate odors but if you are avoiding carbon (like I am) then try Seachem Purigen. I use it and have crystal clear smell free water. I think having live plants helps eliminate toxins that cause odors as well. And purigen can be used safely with live plants. It is win/win.

Carbon will usually eliminate odors but if you are avoiding carbon (like I am) then try Seachem Purigen. I use it and have crystal clear smell free water. I think having live plants helps eliminate toxins that cause odors as well. And purigen can be used safely with live plants. It is win/win.

Thanks guys I solved the problem. To bring up water temps in the system in this small 14 by 7 foot room I sealed it off and directed a heating duct inside the room (Yes I know heating the water and insulating the 300 gallon tank would be more efficient but a heater is not in the budget right now). Anyway it appears sealing off the room was intensifying the odor and once I opened it back up all is well. Kind of like eating chili for dinner and flatulating in a small room all night as you sleep.

Unfortunately I do need to feed these fish more than typical as they are quite small at only 3/4 inches and there are a about a 1000 of them. So daily to every other day partial water changes are the norm along with cleaning up any feed that has sunk to the bottom. At this size sinking feed is my only option.

Edited by az9, 05 February 2010 - 09:04 PM.

I would look for a dead fish, rotting food, something, somewhere, with a healthy cycle all you usually smell is smell like potting soil.

Carbon will usually eliminate odors

Yeah, for about 2 days until the low-grade carbon becomes useless and then smell returns. I'm not arguing, you're 100% right. I just think carbon is basically useless and that the source should be found!

Like ^^ said, a well-cycled tank should have no bad smells....it should smell "earthy".

Bad smells in my experience are nearly always from over feeding/cycling issues or having a box of dead coral behind the aquarium system that someone overlooked (probably not an issue in your case ).

I would look for a dead fish, rotting food, something, somewhere, with a healthy cycle all you usually smell is smell like potting soil.

I did find a fair amount of uneaten feed under the RBC I missed. I need to back off on the feeding and remember the water is only 62 F. so there isn't a lot of feeding going on vs. typically summer temps I feed at. Sure hope i can afford in programmable submerged heater soon or growth isn't going to be very impressive.

Anyway the odor problem is pretty much over.