Can't ger rid of mt nitrAte?? Can anyone help?

[Fishless cycle]

I've fishless cycled 4 tropical tanks successfully, but this current one's nitrate levels won't fall below 40ppm. I don't understand?

I've being cycling using ammonia. It usually takes me about 3-4 weeks but I'm in week 8 and although my ammonia and nitrite are cycled and not showing on my API liquid tests my nitrate is and won't budge. I've done 5 90% water changes and still it shows. I have cleaned the tubes to the filter. Cleaned my filter. Checked for no dead plants, kept the gravel shallow. I'm using RO which I use in my other tanks which shows as zero nitrate in my other tanks but its still showing up at 40ppm even after a 90% water change. I even added a nitrate reduction bag to my media to keep nitrates down.

The lfs says that it's not harmful at that level to tropical fish but my beta has been in zero nitrate for months and I don't want him to suffer when I add him to the new tank.

I have a few rocks in the new tank but I boiled them before adding them.

Does anyone have any clues? It's driving me crazy and the RO water changes are becoming expensive!

 

[Fishperson]

What test kit are you using?
cut down on the amount of ammonia that you are adding. How high do you normally dose it?

 

[Fishless cycle]

What test kit are you using?
cut down on the amount of ammonia that you are adding. How high do you normally dose it?

I'm using the API liquid test. I've been dosing 2ml of ammonia as its an 80 litre tank. I've stopped doing that now and I'm just adding fish flakes. Do you think I need to take out all the gravel? I'm not sure where the nitrate is coming from. Could it be the plants - they are all new from the shop but quite a few dead leaves appear each day which I remove.

 

[Fishless cycle]

What test kit are you using?
cut down on the amount of ammonia that you are adding. How high do you normally dose it?

I normally dose up to 3ppm. It will only be for a couple of fish though... My beta and I might get a small bristlenose to keep algae under control and maybe a few neons but that's it.

 

[Fishless cycle]

Okay so to keep you uptodate - I have finally found out where the nitrAte was coming from. After yet another 90% pwc with RO and still nitrAte showing I decided to take out a large stone that was in the tank and check it out. The lfs where I bought it from told me it wouldn't be a stone that caused nitrAte... well, I dropped the stone into a bucket which had pure RO in and within an hour the water had 30ppm nitrAte!!! I am over the moon.... Once I've changed the water I can add my patient fish into healthy cycled water.... woohoo!

Tomorrow I'm going back to the lfs to ask for a refund on the stone and for a refund on all the RO I've bought from them... Will work out to be around £50-£60 at least. Let's hope they put the customer first!

 

[Fishperson]

Wow, thats interesting!
As my mom would say, "who woulda thunk it?!"

 

[Coyne]

So your problem (and solution) got me thinking... "Hey, Ive got a rock that I dont know anything about that Im about to put in my newest tank."

I had already given it a sound scrubbing and had given it the vinegar test (no fizz), so I thought I was good to go. But after what happened to you I decided to let it sit in a bucket of water over night and see what happens. I tested the water beforehand and had zeros across the board (which is normal for my tap water). But after a little over 12 hours in the bucket, I now show nitrates between 0-5ppm. I had no idea rocks could produce nitrates!
I really like the rock, so Im going to continue to experiment with it over the next week to make sure that I didnt get a false reading and also to get a better idea of how quickly nitrates are being produced.

Im sure this comes as small compensation, but your problem likely saved me from the same issue. Just wanted to say

 

[Fishless cycle]

So your problem (and solution) got me thinking... "Hey, Ive got a rock that I dont know anything about that Im about to put in my newest tank."

I had already given it a sound scrubbing and had given it the vinegar test (no fizz), so I thought I was good to go. But after what happened to you I decided to let it sit in a bucket of water over night and see what happens. I tested the water beforehand and had zeros across the board (which is normal for my tap water). But after a little over 12 hours in the bucket, I now show nitrates between 0-5ppm. I had no idea rocks could produce nitrates!
I really like the rock, so Im going to continue to experiment with it over the next week to make sure that I didnt get a false reading and also to get a better idea of how quickly nitrates are being produced.

Im sure this comes as small compensation, but your problem likely saved me from the same issue. Just wanted to say

Hey
I'm glad I could be of some help. However... I have had an update today and found out that it was my test kit and not the rock! I found out that my test kit has been reading wrong as I went to another lfs and we both tested the same water with different kits and my API nitrate test bottle was reading nitrate at 30-40ppm when the JBL and Red Seas kits were reading 0.75ppm!! It's been waaaay off!

However, the vet specialist i spoke to said that some stones and rocks which have tiny holes can carry nitrate and they will need to be immersed in RO for the nitrates to come out. So it is still possible for stones to carry nitrate.

I've just bought the Red Seas Nitrate test kit as its accurate and I'm keeping the API liquid bottles for ammonia, nitrite, ph etc... which I believe are accurate.

My fighter fish went into his new 80 litre tank today... he's spoilt but I'm relieved that the water is healthy for him. He's exploring at the moment

 

[Coyne]

Thats why I wanted to keep testing it. I figure that if the rock is producing nitrates then I should see an increase the longer it stays in there.
Its good to know there is a solution should it prove true.