more nitrates

[rbell219]

I have been battling nitrates for a while and with good results from advise here--thanks to all.

Now---i can't seem to get them below 7.5. I am doing 50% water changes every week. My supply water reads 0ppm. My test kit is new. Over the course of a week they will rise to 10ppm---7.5ppm 2 days after the water change. I don't test again until before the water change on day 7. I'm not worried, but I am very anal when it comes to the water chemistry and I'm shooting for zero. All other parameters are perfect----0 nitrite--0 ammonia. Ph is stabil at 8.0. I only feed once a day and all the food is gobbled up in a matter of seconds.

I don't add any salt of any kind---would this help? also, any other advice as to why they won't go to zero?
Click the link in my signature for specs. The largest fish is about 2.5" - everyone else is smaller. The loach is about 5" and the catfish are 2" and 3".

[IceH2O]

I'm not sure you can get nitrates to 0..The fish waste and natural decay would make it impossible.Unless you put little colostomy bags on all the fishes and feed each fish seperately to make sure they clean their entire plate.

Everything I've read in this forum and other sites says to shoot for 10 ppm in a planted tank or 20 ppm in an unplanted tank...

I think you should be very happy with 7.5 ppm.

[ghinksmon]

I think you should be very happy with 7.5 ppm.

Ditto.

I think any lower would require a constant stream of new water and an overflow.

[rbell219]

Cool---that's what I figured. I've restocked the tank after a 2 year hiatus from the hobby. Before I always had constant 5ppm----so it's just my over attentiveness kicking in.
I like the colostamy bag idea---i'll let ya'll know how it turns out :dance:

[rbell219]

The colostamy bags don't work......................... :joke: