80 ppm nitrates in 125 gallon

[Irecruitfish]

My opaline gourami passed the other day. I was trying to get rid of it for 2 months but no takers. It was getting bullied by my dolphin cichlid anyway. I have had this 125 running for almost a year and have ton weekly to at most 2 week water changes. I decided to test the water using the API kit and everything else was perfect except nitrates are at 80ppm. The only thing I have done differently in the past month is I started feeding twice a day versus once a day to promote growth. The other thing is I have only cleaned out the FX6 filter once since the tank as been up.

I'm going to clean it out now but can this be the cause of the high nitrates? Or shocking the tank with twice a day feedings?

Stock:
one 6 inch Senegal Bichir
one 4 inch electric blue acara
one 3 inch dolphin cichlid
6 tiger barbs
5 black skirt tetras
one 5 inch African knifefish
3 3 inch syno petrcola(spelled wrong) catfish
one 7 inch fire eel

This is a planted tank(low tech)

 

[philipraposo1982]

How long has the tank been setup??

 

[duanes]

Filters that are not regularly cleaned of gunk often become nitrate factories.
Gunk that is remove from the tank to the filter is not really removed, if in a filters its still in the water column, and like being swept under the rug, where it gets broken down to nitrate.

 

[skjl47]

started feeding twice a day versus once a day

Hello; This adds to the total nitrate load in at least two ways. One, of course, is the food that he fish eat becomes waste products from their metabolism. The other is the bits of food that do not get eaten. This decays and eventually adds to the nitrate load.

only cleaned out the FX6 filter once

Hello; Duanes likely called this one. I clean out the filters more often than this with a very much lighter bio-load.
The filters should have at least two types of media. One is to physically trap stuff like excess food and other things often called detritus or mulm. Some like to "rinse it gently in tank water" and re-use it. I just replace it with new stuff and throw out the old.
I am not familiar with the FX6 so do not know if it has more than one chamber. If it does then a strategy can be to replace one part now and the other later.

Behind the trapping media can be other media that allows water to pass thru and can function a place to have the beneficial bacteria (bb). This can be rinsed out and re-used.

can this be the cause of the high nitrates?

Hello; I think 40 ppm is considered high for nitrates, with the goal to stay at no more than 20 ppm and better below.

Filters that are not regularly cleaned of gunk often become nitrate factories

Hello; This.

 

[Irecruitfish]

How long has the tank been setup??

11 months

 

[souzie]

Agreed with duanes

Think of your filter as the toilet of your tank. If you don't clean it, it gets backed up and spits shiet back out...

 

[Irecruitfish]

Right on thanks for confirming everyone. How often should I clean it? Also, I just finished the cleaning but had two beers and forgot to check the impeller blades. How often should I replace the impeller blades?

Back to nitrates. I'll go back to feeding once a day. Should I do 2 water changes per week to get the nitrates down or will it go down on it's own since I just cleaned the canister and will cut back on feedings?

 

[Drstrangelove]

Assuming the test is correct, assuming your tap water isn't full of nitrates, and assuming you are feeding normally, you would be adding only 2 ppm of nitrates per day from food.

So, to reach 80 ppm, would mean one of two things: you are changing very little water and doing so very infrequently, with a second possibility that you have trapped large amounts of uneaten food inside the tank (filter) which is slowly degrading into nitrates.

As you've admitted to both factors, that would be my guess. Cleaning a filter does not cause high nitrates. Inadequate tank maintenance does however, so in the future, I'd say, given your current stock, do 50% water changes weekly and consistently, and clean out the filter before it becomes loaded with thick gunk. Then, you should be fine.

However, your fire eel and a few other fish will cause those estimates to be wrong before long, so you'll have other issues to address in a while.

 

[TwoHedWlf]

Right on thanks for confirming everyone. How often should I clean it? Also, I just finished the cleaning but had two beers and forgot to check the impeller blades. How often should I replace the impeller blades?

I assume you mean the whole impeller and shaft because they're usually sold as a unit...Every 3-4 years, when it gets too rattly. How much are you changing? It doesn't sound like you're changing much.

 

[pescado209]

I bet it's the filter.. as it's already been stated .

as a point of reference I'm running an fx4 on a 150g with 10 fancy gold fish im cleaning out the filter every 3 to 4 weeks becuae it gets so clogged it won't start( flow water thru) after a water change . I also have a AC110 on the tAnk I clean out weekly , the pump pushes out the media and sponge once the sponge and filter floss are clogged.