[TheApprentice707]

Hey, I do a 15% water change every 2 weeks on my 10 gallon salt tank. Ammonia is always zero but right before my change the nitrate will show 20ppm. After the water change it still reads 20ppm. what do you think i should do?

[King Triton]

What does the water your changeing with have for nitrates ppm?do you have a sump?Sumps can be nitrate collectors and if you change by adding water to sump it stirs up the sump and releases nitrates to tank.If you dont put in high quality water with lower nitrates in it cant go down, are you filtering water through a ro filter?I know Nano tanks are very pop these days but in my 20 yrs of tanks I have found the larger tank the easier to keep stable.I myself wouldnt even attempt a reef any smaller than 30 gal but if it has to be small use RO water and keep changeing.I recently helped a friend of mine out who had nitrates 160 ppm in his tank and couldnt get them down but his tap water was 160 ppm no way for it to lower if he used that water so we used ro water from my place to show him it would lower and we just installed a ro filter at his house last weekend.Now he is down to 5 ppm.I think if ro isnt being used there is no way of knowing what will come out of your faucet some days it could be good water others not so good.Hope i helped

[TheApprentice707]

I was using ocean water that I got from my local fish store. I will get some RO water next time. Can i get it from my fish store or do I need to get a filter.

I want to get a bigger tank so bad, but I don't have a stable place to live really because I am in college. I am 20 years old and I live in an apartment. I don't know how soon it will be until I move again. I can't wait to get a bigger tank.

THanks for your help. I am going to check nitrate or the ocean water that I have. I only have like 2 or 3 gallons left so ill get some RO water and mix the salt myself for the remainder of my changes.

[leebca]

A 15% reduction (from a 15% water change) of a 20ppm solution would reduce it to 17ppm. The difference in 'readings' in a test kit would be hard to tell, if at all. Try a 50% water change.

You may wish to read this: Nitrates - Origin & Controls

[mongoose]

Have you tested your NSW for nitrates before use ?

[King Triton]

ocean water should be great to use I would do a larger water change or have local fish store do nitrate test b4 you buy there water they could be your issue.