Struggle with water quality and high nitrates in cycling tank

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Ap19466

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Hello

I am very new to the hobby having just had a few Danio over the past year. Unfortunately I didn’t know about fully cycling a tank before, had used QuickStart and waited a few weeks before adding the fish.
I am upgrading to a 20gallon tank but the water quality is terrible where I live

pH 8
Very hard quality.

I am day 12 of cycling my new tank with fish food and I am getting
Ammonia 2ppm
Nitrites 0.5ppm
Nitrates 40-80ppm

I was concerned due to the high nitrates having done some recent reading up on the subject, so I did a 25% water change being careful to avoid filtrate and ornaments. The nitrate remained high the next day so I did another water change and no difference.
I tested the water out of the tap and it was 80ppm.

I guess what I would like to know is do I need to treat water in tank to reduce nitrates? If I do, do I do it while tank cycling or wait till fully cycled?

Thanks.
 
Hello

I am very new to the hobby having just had a few Danio over the past year. Unfortunately I didn’t know about fully cycling a tank before, had used QuickStart and waited a few weeks before adding the fish.
I am upgrading to a 20gallon tank but the water quality is terrible where I live

pH 8
Very hard quality.

I am day 12 of cycling my new tank with fish food and I am getting
Ammonia 2ppm
Nitrites 0.5ppm
Nitrates 40-80ppm

I was concerned due to the high nitrates having done some recent reading up on the subject, so I did a 25% water change being careful to avoid filtrate and ornaments. The nitrate remained high the next day so I did another water change and no difference.
I tested the water out of the tap and it was 80ppm.

I guess what I would like to know is do I need to treat water in tank to reduce nitrates? If I do, do I do it while tank cycling or wait till fully cycled?

Thanks.
I use a 50/50 mix of tap water and RO water to reduce the hardness of my water and I think by using the 50% RO water you’ll be halving the nitrate figure...
 
It won’t hurt the cycle to go ahead and take measures to reduce the nitrate and will probably help keep algae growth in check.

One thing to keep in mind is that if you’re going to be moving fish from the old tank that are used to the higher nitrate level they might be stressed by the drastic change when going into the treated tank. You might consider trying to bring the old tank slowly closer to the new nitrate level before transferring them.
 
pH 8
Very hard quality.
Not the only way to know if your water is hard or soft is to test the GH (general harnesss of the water. GH Is a measure of calcium and magnesium. PH does not indicate the harness of the water you can have very soft water with a PH of 8 and ahard water with a low PH. Knowing the GH and KH of your water would help a lot.
 
Not the only way to know if your water is hard or soft is to test the GH (general harnesss of the water. GH Is a measure of calcium and magnesium. PH does not indicate the harness of the water you can have very soft water with a PH of 8 and ahard water with a low PH. Knowing the GH and KH of your water would help a lot.
You can also look online, you’re local water company has to post all of the information In their water quality reports.
 
Hi Ap, be patient it may take up to 8 weeks for a complete cycle and your readings are normal for the cycle. Please don’t add any fish during the cycle, they will suffer. Ensure you have an adequate filter - in the longer run you’ll only need about 10% water change a week, and do add fish slowly after your readings have stability. Do not fight a battle with the pH of 8, research and find fish that will happily reside in that pH, ask at your local aquarium store they will give you good advice.

Best of luck.
 
If you have 80ppm nitrate in your tap water, it is poisonous to you and any fish, bird or animal that drinks that water and you need to contact the health department and water company.

The maximum safe level of nitrates in tap water in the UK is 40 or 50?ppm. By law, it is not allowed to be higher because it is harmful to things that ingest it.

If you have nitrates in the water, you probably have other harmful substances too.

You should get a reverse osmosis (R/O) unit and that will remove the nitrates and minerals that are causing the hardness. Then add some mineral salts (like a Rift Lake water conditioner for African Rift Lake cichlids) to raise the GH back up to whatever level you require for the specific fish.

---------------
Don't bother testing for nitrates while the tank is cycling because nitrate test kits read nitrite as nitrate and give you a false reading. Wait until the ammonia and nitrite have both gone up and come back down to 0ppm, then start testing the aquarium for nitrates.

If you have an established aquarium with an established biological filter, you can take some of the filter media/ material from the established filter and put it in the new filter to speed up the cycling process. Quite often you can take half the filter media and use it in the new tank and add fish the same day. This means you don't have too cycle every new tank you get.
 
I use a 50/50 mix of tap water and RO water to reduce the hardness of my water and I think by using the 50% RO water you’ll be halving the nitrate figure...
Have been reading up on those and they look interesting but I don’t like the idea of all the waste water for environmental reasons.
I have found a site which as various reservoirs of RO water around the country where you can top up containers and they are open 24/7 which I may look into
 
You can also look online, you’re local water company has to post all of the information In their water quality reports.
Will have to check. I remember on previous test strips for my small tank it was reading a higher value than pH so 9 or 10 I think. I currently have the API master test kit but may have to look into getting a KH test strip
 
Hi Ap, be patient it may take up to 8 weeks for a complete cycle and your readings are normal for the cycle. Please don’t add any fish during the cycle, they will suffer. Ensure you have an adequate filter - in the longer run you’ll only need about 10% water change a week, and do add fish slowly after your readings have stability. Do not fight a battle with the pH of 8, research and find fish that will happily reside in that pH, ask at your local aquarium store they will give you good advice.

Best of luck.
Hi Ap, be patient it may take up to 8 weeks for a complete cycle and your readings are normal for the cycle. Please don’t add any fish during the cycle, they will suffer. Ensure you have an adequate filter - in the longer run you’ll only need about 10% water change a week, and do add fish slowly after your readings have stability. Do not fight a battle with the pH of 8, research and find fish that will happily reside in that pH, ask at your local aquarium store they will give you good advice.

Best of luck.
Thank you for this advice. I am quite happy to wait and let the tank cycle and have been doing a lot of reading about fishless cycling. They do mention that nitrates could halt or at least slow the cycle so I just wasn’t sure about whether it would be best to wait till ammonia and nitrite levels were 0 or try and correct values during the cycle.
I plan to add fish slowly and let them adjust slowly before adding new tank mates but the waiting is sooo hard 🙄
 
Have been reading up on those and they look interesting but I don’t like the idea of all the waste water for environmental reasons.
I have found a site which as various reservoirs of RO water around the country where you can top up containers and they are open 24/7 which I may look into
I’ve just googled and didn’t realise that water was wasted during the RO process. I’m curious though, how is the water sourced for the reservoirs..?
 
If you have 80ppm nitrate in your tap water, it is poisonous to you and any fish, bird or animal that drinks that water and you need to contact the health department and water company.

The maximum safe level of nitrates in tap water in the UK is 40 or 50?ppm. By law, it is not allowed to be higher because it is harmful to things that ingest it.

If you have nitrates in the water, you probably have other harmful substances too.

You should get a reverse osmosis (R/O) unit and that will remove the nitrates and minerals that are causing the hardness. Then add some mineral salts (like a Rift Lake water conditioner for African Rift Lake cichlids) to raise the GH back up to whatever level you require for the specific fish.

---------------
Don't bother testing for nitrates while the tank is cycling because nitrate test kits read nitrite as nitrate and give you a false reading. Wait until the ammonia and nitrite have both gone up and come back down to 0ppm, then start testing the aquarium for nitrates.

If you have an established aquarium with an established biological filter, you can take some of the filter media/ material from the established filter and put it in the new filter to speed up the cycling process. Quite often you can take half the filter media and use it in the new tank and add fish the same day. This means you don't have too cycle every new tank you get.
It could be me reading the test strip wrong but the colour change seems to be somewhere between 40ppm and the next value up (sorry haven’t got the test kit in front of me as at work currently).
So shall I be concentrating on ammonia and nitrite readings till appears cycled? Then do a few water changes and gravel clean to remove the fish food and then check nitrates and pH and see a true value for the water quality?

I know the water quality is bad as the mineral deposits have messed up several kettles and the water always tastes a little funky out of the tap so always have to use a filter jug. Just always put it down to where I live.
 
I’ve just googled and didn’t realise that water was wasted during the RO process. I’m curious though, how is the water sourced for the reservoirs..?
I’ve just googled and didn’t realise that water was wasted during the RO process. I’m curious though, how is the water sourced for the reservoirs..?
It is a company that has these water distribution centres in several locations with 24/7 access apparently you sign up for an account they give you log in details to access the sites similar to self storage company’s. You can go and get RO water at 3.5p per litre with tax added on. It does mention could be used for aquariums

 
It won’t hurt the cycle to go ahead and take measures to reduce the nitrate and will probably help keep algae growth in check.

One thing to keep in mind is that if you’re going to be moving fish from the old tank that are used to the higher nitrate level they might be stressed by the drastic change when going into the treated tank. You might consider trying to bring the old tank slowly closer to the new nitrate level before transferring them.
That’s a good idea. I was thinking of isolating the fish from the smaller tank as have had an outbreak of diodomes
It won’t hurt the cycle to go ahead and take measures to reduce the nitrate and will probably help keep algae growth in check.

One thing to keep in mind is that if you’re going to be moving fish from the old tank that are used to the higher nitrate level they might be stressed by the drastic change when going into the treated tank. You might consider trying to bring the old tank slowly closer to the new nitrate level before transferring them.
thats a good idea. I have been thinking of isolating the fish in the smaller tank for a couple of weeks as had an outbreak of diotoms which I don’t want to transfer to the new tank. I could starts acclimatising them to the new water slowly during this time.
 
So shall I be concentrating on ammonia and nitrite readings till appears cycled? Then do a few water changes and gravel clean to remove the fish food and then check nitrates and pH and see a true value for the water quality?
Yes, just test ammonia and nitrite every couple of days until they have both gone up and then come back down to 0ppm. After that, do a complete water change and gravel clean the substrate. Then let it run for 24 hours and test the water.
Make sure the new water is free of chlorine/ chloramine before it's added to the tank.
 

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