Nitrate Help !

[tonyr]

having had carp in my tank for the last 10 months i have now cleaned it out replaced all the sand for gravel and done three water changes using RO water and i can't seem to get the nitrate level down its crimson at the moment all the others nitrite amonia etc seem to be fine its doing my head in cause i want to put tropicals back in any advice would be great thanks

 

[Christine1014]

I'm not familiar really with RO water; that always struck me as something more common in Marine tanks, but have you tested the nitrate levels of the water before you put it in the tank?

Have you vacuumed your gravel?

If you're not using a liquid test kit, try that, as the test strips that you just dip in the water can be really inaccurate, especially for nitrate.

 

[Puffdaddy]

Water changes about 30-50% a day until the readings are about 20 ppm. Live plants help a little too in the long run. I'm not sure why your using RO water but it is not needed.

 

[tonyr]

Water changes about 30-50% a day until the readings are about 20 ppm. Live plants help a little too in the long run. I'm not sure why your using RO water but it is not needed.

confused as to why you think i should not use RO water our tap water is not very good here and the shops always say to use RO but any advise to use anything else would be good its a right pain getting 50 litres every two weeks at £7.00 a time or are they just telling me that so i buy it all the time

Cheers
Tony

 

[Aphotic Phoenix]

The problems with using pure RO water are:

1) RO water is lacking in the minerals that your fish/plants need
2) is lacking in buffering capacity, and is therefore much more likely to experience swings in pH
3) (totally theoretical here but...) I would imagine that "pure" water like RO water would do some odd things to the osmotic pressure on your fish.

It's fine to "cut" your tap water with RO water, or you can purchase mineral replacements for your RO water...but don't use pure RO water.

Is there any waste/debris built up in your filter pads, or gunk built up in the bottom of the filter? Sometimes this decaying matter can cause high Nitrates.

 

[tonyr]

The problems with using pure RO water are:

1) RO water is lacking in the minerals that your fish/plants need
2) is lacking in buffering capacity, and is therefore much more likely to experience swings in pH
3) (totally theoretical here but...) I would imagine that "pure" water like RO water would do some odd things to the osmotic pressure on your fish.

It's fine to "cut" your tap water with RO water, or you can purchase mineral replacements for your RO water...but don't use pure RO water.

Is there any waste/debris built up in your filter pads, or gunk built up in the bottom of the filter? Sometimes this decaying matter can cause high Nitrates.

no i have even taken drastic measures of replacing the filter pads a week ago there is no fish in the tank at the moment,would a total water replacement do the trick

 

[Aphotic Phoenix]

Well if you've replaced the substrate and the filter...your tank is most likely uncycled, and there really wouldn't be much place for the nitrates to be coming from except for the levels that were built up in the water...

What was your maintance schedule like before you decided to change the tank over? How often did you do water changes and/or test water quality?

 

[tonyr]

Well if you've replaced the substrate and the filter...your tank is most likely uncycled, and there really wouldn't be much place for the nitrates to be coming from except for the levels that were built up in the water...

What was your maintance schedule like before you decided to change the tank over? How often did you do water changes and/or test water quality?

because it had carp in it which are very hardy maitenance was not done very often maybe a complete water change is needed and start as if it was a new set up

 

[Puffdaddy]

What do you believe is wrong with your tap water? Unless you have a marine tank RO water is just a waist of money. And yes if your lfs tells you that you have to use RO water they are just trying to make an extra buck off you. No you don't want to change all your water a once. Just do about 30-50% every 24 hrs until the nitrate read 20 ppm. Remember to add a dechloranator to the tap water, such as Seachem's Prime.

edit: just seen the previous posts after I typed this one out. Your best bet is to start from scratch and cycle a new tank.

 

[tonyr]

What do you believe is wrong with your tap water? Unless you have a marine tank RO water is just a waist of money. And yes if your lfs tells you that you have to use RO water they are just trying to make an extra buck off you. No you don't want to change all your water a once. Just do about 30-50% every 24 hrs until the nitrate read 20 ppm. Remember to add a dechloranator to the tap water, such as Seachem's Prime.

edit: just seen the previous posts after I typed this one out. Your best bet is to start from scratch and cycle a new tank.

my mistake just checked tap water amonia and nitrite is 0 mg nitrate 25-50mg would this be ok to use in tropical tank if i put tap safe in it instead of paying for RO

 

[rdd1952]

because it had carp in it which are very hardy maitenance was not done very often maybe a complete water change is needed and start as if it was a new set up

Here in lies your high nitrte problem. Nitrate can only be removed by water changes and carp (is it trruel carps, if so I hope you have a huge tank as they can grow to well over 50lb) are extremely big waste producers. The only way to get them down is with a very large water change of at least 75% and then weekly 25 to 50 percent WCs.

Edit: Just saw your post saying your nitrate was between 25 and 0 from the tap. In that case, you will definitely have to stay on top of water changes to keep the nitrates down. As a general rule, nitrates are only toxic at high levels but if they are off the chart then you could have problems.

 

[tonyr]

because it had carp in it which are very hardy maitenance was not done very often maybe a complete water change is needed and start as if it was a new set up

Here in lies your high nitrte problem. Nitrate can only be removed by water changes and carp (is it trruel carps, if so I hope you have a huge tank as they can grow to well over 50lb) are extremely big waste producers. The only way to get them down is with a very large water change of at least 75% and then weekly 25 to 50 percent WCs.

Edit: Just saw your post saying your nitrate was between 25 and 0 from the tap. In that case, you will definitely have to stay on top of water changes to keep the nitrates down. As a general rule, nitrates are only toxic at high levels but if they are off the chart then you could have problems.

yes they are true carp and they are now outside in a pond,they were only fry when i had them only in the tank to help them grow a bit faster i will now do bigger water changes thanks for all your comments they were most helpfull

 

[ArauraDiscus]

Yeah just do a 100 percent water change, that will bring it to the levels of your tap water. It's as simple as that.

 

[rdd1952]

Ok, I misunderstood. I thought they were still in there. Since you are basically starting the tank over, yes, just do a 100% water change.