Nitrate Problems

[realdeal]

I have a 36g FW tank with a Rena XP2 filter. I have 10 small fish, (neons and the like) and 2 High-Fin Tetras. The tank is about 1 year old and cycled.

My Nitrate levels have been off the charts. I thought it was originally due to my lacksidasical water changes but I started changed 25% of the water every three weeks and the Nitrates at the end of the 3 weeks are still off the charts.

My filter media consists of (from the top):
- Microfiltration pad
- Carbon
- Ceramic Rings
- 2 30 PPI Foam
- 2 20 PPI Foam


I clean out the filter about once every 2 months which consists of rinsing the foam, changing or rinsing the Microfiltration pad (depending on how it looks) and replacing the carbon.

I feed the fish a VERY small amount once per day.

Am I missing something? Doing something wrong?

Could it be the filter? In my first go around in the hobby, about 15 years ago, I had a 55g with an Eheim (I think) and don't remember having these problems.

Thanks for you help.

 

[Purrbox]

If the Nitrates aren't coming down then you need to increase the frequency and/or size of your water changes. Many people do 50+% water changes on a weekly basis. Usually this is with sensitive fish like Discus, or with a planted aquarium that is being dosed using EI, but it illustrates that you have a significant range that you can increase your water changes.

 

[neilanh]

The first thing that comes to mind is to confirm that your nitrAte readings are real. What test kit are you using? Have you had an LFS confirm your results?

What is the nitrAte reading from your tap water?

 

[realdeal]

I am using the Freshwater Master Test Kit from Aquarium Pharmaceuticals. I have not had my LFS confirm my readings but I've run several re-tests, all with the same result and I have no reason to doubt my readings.

My nitrAte reading from the tap is 5.0ppm

 

[tawolcott]

What is your nitrate reading? The actual number

 

[realdeal]

160ppm+

 

[CatatonicBug]

160ppm+

I would definitely suggest more frequent water changes. Every 3 weeks is way too seldom. Even 25% every week is not enough if your readings are that high. You might try a 50% every 3-4 days until your readings come down, then 40-50% weekly thereafter, since your tap water starts out with 5ppm. You really want to keep it down under 20ppm.

 

[marchmaxima]

Agree.. Several bigger water changes every few days to get that number right down to < 30ppm. Then, weekly water changes.

 

[tawolcott]

You might want to investigate why they are so high as well. If you've been lacking in the water changes it might follow that the same is true of vac-ing the gravel, cleaning the filter(s) and the pads? It might be worthwhile to start off with a good cleaning then follow a more strict regiment of cleaning and watch how much you're feeding. Big water changes and the same practices are going to get you back to where you are now.

On my 30FW every 2 weeks I:
15% PWC
1/3 gravel vac
Rinse the filters
Depending on how the water looks, recharge the carbon


Every 8 weeks:
30% PWC
high pressure vac the UGF
change the GFO
Rinse/change the filter pads
Scrub any of the ornaments that have any algae

My nitrates stay in the 10-15 range

 

[realdeal]

You might want to investigate why they are so high as well. If you've been lacking in the water changes it might follow that the same is true of vac-ing the gravel, cleaning the filter(s) and the pads? It might be worthwhile to start off with a good cleaning then follow a more strict regiment of cleaning and watch how much you're feeding. Big water changes and the same practices are going to get you back to where you are now.

On my 30FW every 2 weeks I:
15% PWC
1/3 gravel vac
Rinse the filters
Depending on how the water looks, recharge the carbon


Every 8 weeks:
30% PWC
high pressure vac the UGF
change the GFO
Rinse/change the filter pads
Scrub any of the ornaments that have any algae

My nitrates stay in the 10-15 range

What does UGF and GFO mean?

So you are actually changing your filter pads and foam and carbon or just rinsing?

 

[tawolcott]

UGF is an undergravel filter, GFO is for phosphate and heavy metal removal.
I rinse the pads unless they are looking bad, then I change the bad looking ones (one at a time, never all at once).
I only run carbon if I think it looks like the water needs some polishing. GFO I run all the time since my local water has some phosphate issues.

I also alternate between RO/DI and tap water also since I run the RO/DI for the SW tank.

I run a UGF and a canister filter

 

[realdeal]

Thank you all for your helpful advice.

Does the filter have any affect on Nitrate? I have the Rena XP2 however, it seems that a lot of the water that goes through the canister probably does not even pass directly through the filter material because there is a lot of extra space in the canister, on the sides of the baskets.

 

[tawolcott]

if you don't keep the material clean, yea... All the gunk increases your nitrates. Maintenance is the key for that stuff, unless you move to SW where you would be best to simple remove them all together