Nitrate Levels Too High For My Fish?

[Katanafish]

 I have recently completed a fishless cycle on a 200 litre aquarium, it is planted and has bogwood and rocks - so plenty of hiding spaces etc.
 
I have now stocked the aquarium with the following (all juveniles):

• 4 x keyhole cichlids
• 2 x kribs
• 1 x BN Plec

I have nitrate levels that are registering at about 40ppm according to the API test kit (ammonia/nitrite and both nil) and I am worried that this nitrate level is too high with regards to the type of fish that I stock?
 
Also, 25% water changes are having little impact since my tap water is running at about 20ppm nitrate. I have also obtained a recent water quality report from my water company that puts nitrate levels as high as 35ppm.
 
Do I need to be concerned and take further action or will the fish just be fine in ~40ppm nitrate water?
 
Thank you for any help.
 
# Edited to clarify that I completed a fishless cycle and then stocked fish.

 

[DeanoL83]

I haven't had any experience at all with the fish listed but are there any live plants that you could add to help reduce the nitrates?

I know you can't have live plants with some cichlids but there might be some tougher ones you can try. Anubias? Or floating plants like frogbit or water lettuce??

Sent from my D6503 using Tapatalk

 

[LyraGuppi]

Keyholes and kribs don't bother plants so much, so you could try adding in some to try and dent the nitrate levels. Fast growing stem plants can help, (hornwort, pennywort, cabomba, and others) or you could try floating plants like Deano said.

 

[gmc1]

I think the oP said it was planted.

 

[techen]

Over time your fish will adjust to the already high nitrate level, I've seen fish live in nitrates over 100+. I wouldn't worry, If your fish look healthy, eating and such. Relax

 

[AbbeysDad]

I disagree with the presumption that just because fish seem to be surviving in water with high nitrates, everything must be fine.
Experts agree that long term exposure to high nitrates definitely causes harm to fish in the form of lower immune systems making them more susceptible to injury healing and disease along with a shorter lifespan.
 
40ppm is considered an absolute maximum acceptable level and since you're at 40ppm and your source water at 20+ppm won't reduce much, if any, your tank nitrates will only increase. Plants are an aid under most normal circumstances, but your's is a bit extreme. Although I might add some floating Anacharis anyway as it is a nitrate sponge.
(sidebar: I know this subject very well as I have high nitrates in my well water due to a farmers field across the road from my well that gets copious amounts of manure AND chemical ferts.)
 
I was previously collecting water from my basement dehumidifier until I came to realize that for some strange reason it was extremely high in ammonia. I also have modified an API Tap Water Filter by filling it with (rechargeable) API Nitra-Zorb to filter nitrates from my well water. (note: Nitra-Zorb pouches can also be used in your filter to adsorb nitrates).
You will also need to take steps to keep nitrates low...rather than be redundant see the post I made on this very subject....
'Established Tank Problem, Asking For Any Advice'
 
Good luck and keep posting.

 

 

[Byron]

I agree with Michael.  Nitrates being safe is one of those "myths" that have been in this hobby for some time, but more recently has been challenged and proven inaccurate.
 
Nitrates should be kept below 20 ppm, and as low as possible beyond that.  Some fish species have been found to be more susceptible than others, and this brings me to the cichlids mentioned in post #1.  Dr. Neale Monks recommends nitrates no higher than 20 ppm for cichlids, and has written that cichlids would appear to have problems if nitrate is higher.  The information on the cichlid forum site is the same, where nitrates have been linked to hole in the head disease and Malawi Bloat.  Now, when I say "linked," I mean that the nitrates weaken the fish sufficiently to make them more susceptible to health problems that otherwise the fish might easily fight off.
 
Michael has experience with source water nitrates, and I suggest checking into his linked thread.  Keeping nitrates low will without doubt mean healthier fish.  There is sufficient evidence of this; at the very least the nitrates will slowly weaken the fish, and this of course is where trouble always begins.  Nitrate like ammonia and nitrite are forms of nitrogen, and all are toxic to fish; it is simply the level and exposure that varies, but we shuld remember than the natural waters in which our aquarium fish originate are so low in nitrate it is usually non-measurable.
 
Byron.

 

[Akasha72]

my nitrates run at around 40ppm (the nitrate test is the main one for known being inaccurate) and it's been much much higher than that in the past. I have a tank that is so fertile right now that I've got members wanting me to find out the formula, bottle it, and start selling it!
 
I've got baby fish popping out from everywhere and I've got plants flowering and creating new plants all over the place. Just this week I too 34 amazon sword plantlets to my lfs and those came from just one mother plant. The same plant produced the same amount around 8 weeks ago. 
 
I admit I'd prefer the level of nitrate to be lower but common sense says - if the fish were all that bothered they wouldn't be breeding like rabbits and nor would my plants.
 
Relax a little 

 

[Byron]

I am not going to argue this, but I would ask you to read the blue citation in my signature.  We cannot possibly "know" that all is well just because the fish don't die.  None of us has any certainty as to what is actually taking place in the fish's metabolism.  Frequently lifespan is the most reliable clue, but when the fish dies is a bit late to attempt corrective action to provide a healthier environment for longer.
 
We do know without any question that nitrates will kill fish if the level is high enough or over time when lower.  These values vary with species, so it is clear that nitrates are harmful.  Setting a "limit" may give us false expectations, so as Dr. Monks said to me, keeping nitrate as low as you can is going to be better in the long run.

 

[Akasha72]

you know ... I can't help wondering how the heck my Dad kept all his fish alive, well and breeding way back in the 70's and 80's when a water change was something they saw once a year if they were lucky. We had guppies that lived for 5 years plus way back then ... I just don't know how we did it 

 

[AbbeysDad]

@Akasha72 - It's not surprising that plants grow well in a high(er) nitrate environment, after all, nitrogen is a fertilizer. The high nitrates in my well water is the result of petro-chemical fertilizers used on the 95 acre farmers field across the road!
If it's a plant only tank, then I guess it's okay, but a fish tank is another story. This makes me think of some planted tank enthusiasts that blast their tank(s) with high light, high ferts and CO2 to promote plant growth...but is this best for the fish?...I don't think so.
 
Again, as Byron pointed out, the nitrates in natural waters where these fish originated are so low they are virtually not measurable.
 
It is also not uncommon that very poor conditions results in a flurry of breeding activity...in nature this is species survival.
 
For a time, I too had some trouble relating this to experiences in my youth. In the 50's and early 60's my mother had a 5g tank...one of those old metaframes with a slate bottom. It had a bubble-up filter (w/activated carbon and filter floss) and just enough gravel to cover the bottom. It rarely got a water change and always had a 1/2" layer of mulm on the bottom. Five of the most beautiful, large fish that remained healthy. Then I remembered that there was sufficient evaporation for routine top offs AND she always had a good layer of floating Anacharis plants (known to be a nitrate sponge). It goes to show you that in addition to the activated carbon removing impurities AND what plants can do to purify water. And the top offs instead of water changes...I surmise that our water hardness was such that the minerals in the top off water merely replaced minerals used by the fish and plants... go figure.

 

[StevenF]

 
he high nitrates in my well water is the result of petro-chemical fertilizers used on the 95 acre farmers field across the road! If it's a plant only tank, then I guess it's okay, but a fish tank is another story. This makes me think of some planted tank enthusiasts that blast their tank(s) with high light, high ferts and CO2 to promote plant growth...but is this best for the fish?...I don't think so.

Just a note the nitrate fertilizers used on farms are sodium nitrate, potassium nitrate, and calcium nitrates.  petrolium is not used to make then and is not a raw material for any of the components in nitrate fertilizer.  Furthermore chemist refer to nitrate fertilizers as solts not petrochemicals.  Petrochemicals are used to make insecticides not the salts used in fertilizers.  
 
The toxic affect of nitrates has nothing to due with Petrochemicals (which is not used to make them).  So adding fertilizers into an aquarium will not make it more toxic to fish than a pond with equivalent levels of natural fertilization in the water.  

 

[AbbeysDad]

Synthetic fertilizers are often derived, in part, from petroleum products like natural gas or petrochemicals.

 

[Katanafish]

Just wanted to thank everyone who has contributed for their valued opinions. It seems to me that fishing living with nitrates is like people living in China - you can be fit, healthy, go to work just like anywhere else in the World but constantly breathing in the pollution means you would be lucky to live longer than 50yrs and not die of cancer. None of my in-laws lived to their 60s and they all died of cancer despite being incredibly strong and resilient in their youth. Based on that I intend to drastically reduce nitrate levels in my aquarium - I'm just figuring out how best to do that.
 
I was about to buy one of these RO filters but after contacting the seller I found it is unsuitable as it requires input water of less than 0.1ppm iron and my water quality report puts iron at 100ppm. I have inserted Fluval Poly/Clearmax pads in to my U4 filter but they have made no measurable difference in a day. Any further advice about bringing levels down and RO filter choice would be welcomed.

Thanks so much

 

[AbbeysDad]

@Katanafish - I do not know if your water is so hard you need to reduce/soften with a mix of RO water? Good RO systems can be somewhat expensive and may require an additional pump if your water pressure isn't 50-80 psi. Also, they need a waste line as there is approximately 4 gallons of waste water for every gallon of RO water produced.
 
There are many in-line nitrate filters that with a simple faucet adaptor you could use to remove nitrates from your source water for your partial water changes. As one promising example, Check out Crystal Quest Countertop Replaceable Double Water Nitrate System on Amazon.
Again, please review the post I made in "Established Tank Problem - Asking for Advice." where I list several tips about nitrate reduction.
 
With the appropriate lighting and a heavily planted tank, nitrates may be much less an issue as the plants will use ammonia and/or nitrates as a nutrient. Plants not only add natural beauty but are another dimension in creating a balanced eco-system in your fish tank.
 
I'll also add a 'thumbs-up' for API's Nitra-Zorb. I use Nitra-Zorb in a spent API Tap Water Filter cartridge to filter nitrates from my well water (that I then use for weekly partial water changes). But the pouches are ALSO extremely effective in your filter to remove nitrates. Best of all, the resin pouches can be recharged and reused many times by soaking in ordinary salt water.