View Full Version : How salt controls nitrites

07-26-2007, 08:07 PM
Well I've had my QT (6' POP tank) setup for about 8 weeks now, but I can't seem to get the nitrites to drop. Here's the vital stats:

PH 8.0

Nitrates .25

Ammonia 0

Nitrites 2.0 +

KH 10 drops (190ish)

I feed almost nothing, water changes every 3rd day or so, clay every other day (1/2 tbp), filter - KW sand filter (55g), + 55g SC half filled with buffer pad. Total ~500g or so. Load 50 3" tosai 1 16" asagi (asagi recently added). I've kept the salt @ .3+ for the duration, and the fish seem great, very active. I just don't know why the ni won't drop. The wc's seem to do little to nothing for the nitrites. Is it possible to have a filter that can handle the ammonia but not the nitrites?

Any advise will be greatly appreciated!!

Thanks, Chris

07-26-2007, 08:14 PM
Is it possible to have a filter that can handle the ammonia but not the nitrites?

Patinece Grasshopper...yes that can and does exist on a regular basis. It can take anywhere from 6 week to 12 weeks or more for the nitrogen cycle to get established. It might even take longer using a sand filter...You've got a lot of fish in there...........the salt will protect the fish so be patient..:punk1:

07-26-2007, 10:25 PM
I thought I read somewhere that salt will not protect beyond 8 weeks, koivet maybe, so this is my cause of stress. Is there any truth to this. If the fish are any indication, they seem happier than pigs in sh*t. Maybe I should just listen to them and relax. :yes:

07-26-2007, 10:53 PM
Listen to the fish.........All the salt does is to provide chloride ions. They and the nitrite ions ''compete at the gill surface to see'' which ones will get picked up by the chloride pumps in the gills. As long as there are more chloride ions than nitrite ions... they win.

There would be a point where the small amounts of nitrite that was being picked, up would start to have a toxic affect on the blood/hemoglobin. You would see signs of piping or hravy breathing. So unless the nitrite levels were through the roof and for a very extended period, the salt should protect the fish.

If a tank or pond hasn't cycled ...both NH3 and NO2 @ 0.0ppm...within 12 weeks then there are other factors within the system that need attention.

By looking at the numbers that you've posted your tank isn't even close to being cycled. Like I mentiioned before you've got a lot of fish in there...is there any fully cycled media around that you can move over?


07-26-2007, 11:01 PM
No unfortunately I don't have any matured media (still working on the "big pond"). I could probably cull a good amount of the tosai if it would help. In fact I could cull most if it protects my asagi. I just don't understand how the filter can keep the ammonia at zero, but not even touch nitrites. :confused:

Thanks for the input, Chris

07-26-2007, 11:14 PM
Two very different bacteria...the group that oxidizes NH3 to NO2 are very quick to establish themselves, where as the next group are slow as hell.
They are starting to work or you wouldn't have any NO3 at all.

What you'll find is that once they get going that NO2 level will drop very quickly, like almost overnight.

If you can drop the bio load all the better. How big is this main pond going to be since you bought 50 tosai

07-27-2007, 09:27 AM
nice explanation Graham, might have to take this to the library