August his original post stated nitrites not nitrates. This sounds like he's
going through a cycle if its nitrites, but you are correct about the Nitrate
and reducing them. More frequent water changes are needed to reduce the
Nitrates. For nitrates, you should be 15 ppm or less Nitrites should be
zero.


ugust West" wrote in message
...
What happened is the first water change removed 40% of the nitrates.
Leaving 60% in the water. The second water change removed 20% of those
nitrates, not another 20% of the original level. So even though you have
changed 60 % of the water, you only got 52% of the nitrates.

If possible, changing aboout 70% and then another 70% will drop the levels
significantly. That should drop your nitrates by about 90% from the
current level

Are you using R/O water? The tapwater in my neighborhood has low levels of
nitrates in it. Over time, this built up in my tank.

Another thing I found way back when was a waste buildup in the hose
leading down to my filter under the tank.
"SCAFFMAN" wrote in message
. uk...
i have a 90gal tank

of late the nitrite has been very high,

even after a 40% water change and a 20% water change a week later

i havent lost any fish of late and have reduced the food, and missing
feeding on some days.

any pointers



thanks