High Nitrite & Nitrate levels in tap water

Question
QUESTION: Hello,

I have set up my 55 gallon aquarium about 3 months ago. I let the tank cycle for about 2 weeks before adding fish. For awhile I had my water in excellent condition, I have added 4 Full grown angelfish, An Elephant nose, a Ghost Knife, a Rainbow Shark, and a few various Tetras.

About 3 Weeks ago I had to buy a new filter (Fluval U4 internal filter good for 65 Gal.) as the previous canister filter started leaking. Ever since then I have had very high Nitrite & Nitrate levels in my tank and can't seem to get them to go down. I do 20% water changes weekly and add Cycle to the water twice per week. This still does not help.

Recently I realized that it is the tap water that has high levels of Nitrite and Nitrate. What can I do to the water to get around this?

Any help would be appreciated, I would hate to start losing fish do to this problem.

Thanks, Dave

ANSWER: Hi Dave,

Okay, some things definitely stand out to me here.

1. Adding cycle to the water is a mistake.  Never add anything to old tank substrate/water.  In fact, if you can avoid it, never add anything to the water, period.

2. Never add tap water to an aquarium.  Add filtered water only.  Never use a dechlorinator.

3.  Fluval U4 internal filter - rated at 65 gallons.  The people who rate these use a system.  They take the flow/gallon ratio that is a "rule of thumb" amongs aquarists and they market it using that well-known rule of thumb.  The fact is ANY canister filter unit is going to become a nitrate/nitrite factory.  That is how they function.  They are under-rated.  Secondly, pet stores tell you to change them out monthly, when in fact, they are need cleaning weekly.  So, if we use this knowledge and add it to the canister filter you have inside your aquarium, you have mistakenly sunk a boatload of nitrates into your tank, and house it there.  Of course it's going to dissipate into the water...that's how they run.  I advise highly, any chance I get, to change over to a wet/dry filter under the tank, with aeration and a non-capped lid, rather than using a canister filter, but if you can't do that, then add a HOB filter to the setup.  Perhaps another rated for 65 gallons, and I would be willing to bet the added flow helps deterioriate some of the problems.

4.  Flow - Flow is essential in an aquarium.  If there is debris settling on the bottom, how can any filter do its job?

5.  Vacuum out your substrate.  Your substrate should be cleaned monthly unless it's a live-plant aquarium.

6.  The model of your filter is made more for a turtle or amphibian tank than for an aquarium.  

7.  Cycle - You have no need for any product.  Your tank is 3 months old.  It has cycled, and is done.  

8.  Ammonia is off the charts with high nitrates, we can just assume this without a test.  Please add Zeolyte crystals (Petco - $5 per container) to a net and submerse it in a flow, maybe in a filter, someplace.  If you do get a HOB filter, please submerse it behind the filters there.

The answer is in the question. :) ie: "About 3 weeks ago I had to buy a new filter...Ever since then I have had very high Nitrite..."

Nitrites are very, very dangerous in an aquarium. Therefore, we need to get this taken care of today to the best of your abilities.

Please take out at least 40% of the water today, and replace it with filtered water. For me, at my local Food Max, I bring a 5 gallon water bottle (in my case, 18 lol) and fill them at the rate of $1 per five gallons.  It's really not that expensive when weighed against the cost of fish, chemicals, etc.  Using this removes the need for any chemicals and all negative materials are filtered out prior.

Your Tetras and Angels will thankyou immediately for filtered water. :) They love it.

My last suggestion is to take the tap water down and have it analyzed properly.  If you are getting nitrites and nitrates in tap water, it's dangerous to human beings.  That comes from poop.  Somewhere, something isn't filtering.  I know I'm a fish expert, but as one fellow person to another...please don't drink any tap water with poop in it.  There are so many diseases floating around which aren't killed if the chemicals aren't even able to kill off the Nitrates and Nitrites.  Aides and Hepatitis are the two main ones coming to mind, not to mention...nobody wants to drink poop water.

Good luck and I do believe your filter is causing most of this, but if not, then it's still under-rated and adding a HOB filter on the back is a great idea.

Happy holidays Dave.  Please feel free to follow-up with more questions.  By the way...Elephant Nose fish are my favorite fish of all time.  They should be kept in schools.  No less than six.  They communicate using electric impulses, through their noses.  They're quite entertaining and sad also. When one of mine passed away, the others hung around him and tried bringing it back to life.  Remember, they require worms to survive and live food.  Flakes will not be sufficient.

Happy fish-keeping!

Renee

---------- FOLLOW-UP ----------

QUESTION: Thank you very much Renee, you have been very helpful. I have done as you have said. I went and bought a 70 gallon Aquaclear HOB filter and removed the internal filter after squeezing all the dirt from the previous filter into the HOB filter. I also did a 40% water change with filtered (reverse osmosis) water from my local grocery store.

The nitrite (no2) levels have dropped significantly to 0.3ppm, however the nitrate (no3) levels still seem to be quite high. PH is neutral at 7.0 and there is no ammonia. I will keep checking the levels over the next week to make sure everything remains okay.

Is adding a new filter with new clean media etc. going to create any problems in the tank?

PS. I checked the tap water, you are correct there is no nitrite or nitrate in the water. I just thought this was the case because just after I would do a water change, my tank already had high levels.

Thanks again.

Dave

Answer
Hello again Dave,

If the levels haven't come down to .5ppm, or lower, you can do another partial water change in 3 days.  

You have another issue to consider.  The gravel.  It has acted as a Nitrate factory since the cycle, because there were so many nitrates in the water.

It's got to be washed through.  Don't boil it or use a chemical on it, that would kill all the anaerobic bacteria in it.

Instead, place it in a 5 gallon bucket and move it around until all the debris comes out.  My guess is it's quite bad.

Then, place it back into the tank, and vacuum it bi-weekly or monthly.  For you, I suggest bi-weekly at first.  When things level off, go to monthly.

Change out the filters in the HOB at least every month.  If you are only using the one HOB, you might consider a second, matching one as well for the other side.  

Your nitrites should never be higher than zero.  Your nitrates, no higher than 10ppm...and that's pushing it.

Dave, I'd also take a look at my feeding schedule and type of food being fed.  I haven't asked you this, because I assume you're feeding these fish what they require in nature...tubiflex worms (blood worms), and algae pellets?

If not, I suggest a flake food, but the Elephant Nose and the Knife will require live food...please make sure to feed them properly. (I threw this in even though you haven't asked, because so many starve them inadvertently to death.  It takes months for the poor things to die).

As far as the cycle goes, there will always be a small cycle when you wash the gravel, but it should be over in a couple days, if you don't use a chemical or boil it.  It just needs the poop and debris removed from it.  The fish can't live in that and I believe that the nitrate levels are high because of the previous water conditions, and invisible settlement into the gravel.

You will not require a chemical to cycle it.  Let it cycle.  Fish can be in the tank with the clean gravel.  It will work itself out within a week and you will be glad you cleaned it out.

If you don't want to wash the soil, please, at least siphon it out with a tank gravel cleaner.  They are about $20, but worth their weight in gold.

It sounds like you're on the right track, Dave.  Good job.  I hope to hear back that the tank levels off and you can finally sit back and enjoy it.  Afterall, that's what it's about. :)

Happy fish-keeping!

Renee