how much of a wc is needed?

[sinner]

we did a 10gl wc this morning. I just tested the water and there is no difference. (i'm testing for nitrates -there way too high).
Do i need to wait longer to see results?
How many gl do i need to change in order to make the nitrates go down? should it be all at once? or by smaller wc?
I can take a water sample to the lfs on friday (closed tomorrow) and see if they get the same.
all inverts and fish are eating and moving around as normal.
thanks for any help.

 

[njdiver]

How big is your tank???

 

[richard rendos]

I usually wait at least a day or two between water changes if there is a problem.
When you do a water change, the nitrates should go down in proportion to the amount of water changed. So if you do a 25% water change, the nitrates should go down 25%. If they do not, check it with another test kit. Test kits do sometimes give inaccurate readings.

 

[mr . salty]

And how high are those nitrates???In extreame cases,up to 100% of the water can be changed at once.But this is only as a life saving,last ditch attempt to save your fish...Up to 50% can be done with little or NO affect on the bio system....Normal water changes should be between 20-25% of the total tank volume...

 

[trompet3]

Also test the water you are using for the change. If it has nitrates in it, you're only replacing bad water with different bad water.

 

[sinner]

it was my kit, my water condition is great! But my kit showed over 180 nitrates before and after the water change. I had ***** test my water they did a great job.
Sinner

 

[mr . salty]

If your ***** is anything like most *****'s across the nation,I would not trust thier test either.Just too be sure take a sample to a GOOD FISH STORE...