API Test Kit

Hi guys,

I just got an API test kit at the weekend and my nitrate test came out a bright blood red. I'm guessing this is between 80 ppm (which is an orangy red) and 160ppm (which is a browny red). Would that be correct?

This is a 260 litre tank and has been running for 3/4 years. I do a 25% water change every week but miss the odd one. All the other water tests were fine.

Would this nitrate level really be harmful to fish because i've never really had any deaths or should i start doing daily water changes to get it below 40 ppm?

I also have a 550 litre tank and this had the same result so daily water changes for both would be a big job and would have to invest in more containers. Not looking forward to these fecking water charges either!!!

Thanks for the help,

Alan.

I assume you are running a marine tank? Regardless of marine or freshwater, nitrates should be kept to a reasonably low level. In a marine system, there are several recommended safe levels depending on the tank set-up.
Generally it is recommended that you keep the nitrate level below 100 ppm for a fish only system, 40 ppm for most reef tanks, and below 20 ppm for systems hosting anemones.
The nitrates occur as a result of the nitrogen cycle, ammonia converts to nitrites, the nitrites in turn to nitrates. Most people feel the only way to remove the nitrates or keep them low is through a regime of water changes. Not necessarily true. And no, I am not suggesting for a moment that you should stop doing water changes There are several other options for removing nitrates. Macro algae in a marine system for example absorbs nitrates, the more algae or higher the growth rate, the more nitrates absorbed. Some filters such as trickle filters are very efficient at removing nitrates. There is also the option of using a deep sand bed to convert nitrates into nitrogen by means of anaerobic bacteria . I know ! everyone tells you to avoid anaerobic bacteria in an aquarium, and for good reason, however, the right anaerobic bacteria can be beneficial too!
There can be significant detrimental effects from having no nitrates whatsoever in a tank too, so there is a balance to strike!

Thanks Bill, sorry they are both fresh water aquariums.

Thanks for the info. Will look into ways of getting these levels down

Hi Alan,

Moved to tropical water and health (was under marine)
Are they panted tanks? Plants and moss will remove a lot of nitrates from the water. The best option to get the levels down initially is through water changes though. A deep sand bed will also work in a freshwater set-up too. Only needs a sand bed 45 to 50mm thick. Would recommend doing some research on it rather than just implementing it though, Disturbance of the anaerobic areas of the substrate can lead to complications in several ways, kill off of the anaerobic bacteria and also release of potentially harmful gaseous compounds such as sulphur dioxide.

Here are a couple of good links -
www.bestfish.com/oldtank.html
www.aquaworldaquarium.com/Articles/TonyG...ts/silent_killer.htm

Cheers,

Bill.

Sorry Bill didn't see that.

No they're not planted tanks. The fish i have would just eat them.

I've a small stone substarte so a sand bed is out.

I think i'll just start trying the daily changes to see if that has an effect.

Any idea if a bright red colour with this test is around 100 or over 180?

I got my API master kit today as well, at least now i can test my water again to make sure my Rams are as happy as they look

Let us know how you get on. I was a bit dissappointed to see my nitrate reading cos give these tanks a good scrub and water change weekly.

Not too sure on the colour of the test Alan sorry.
Never got a reading above 50 myself. It could be that its off the chart on the rated results
I find the best way to get a match on the chart is to hold the colour chart up with a good light source behind you and hold the tube beside the chart, best done in daylight beside a window. You will typically see the colour is a reasonable close match to one of the colours on the chart. Makes it easier to see if the shade falls between 2 of the ones on the chart too.
I tend to air on the side of caution too and assume the worst case and react accordingly. That is to say, if the shade you actually get falls between 2 on the chart, go with the higher measurement.
If its darker than anything on the chart, it typically implies you have maxed out the test kits ability to measure it.

Yeah,like Bill,i have thankfully never got a too high of a reading for Nitrate so i never had to look at the higher end of the chart,but since reading this,i whipped the kit out for a look and them colours are rediculously alike,especially the 40ppm and 80ppm ones.........But if your getting a bright red result,at a guess i'd say you are in the 40ppm to 80ppm region and defo not off the chart!!

Ger

Thanks lads, yeah i thought the same Ger. Very hard to tell the diff between 40 and 80

Have to wait till i get home from work before i can even get to my test kit, its all packed away for the time being, Seahorse really know how to transport livestock (ordered 10 neon tetra along with my test kit)

at least i have material available to me for when the time comes and i need to move again, still need to get a few waterbutts though there's no way i'm waiting a month re cycling my tanks, i'm just gonna move the water too

Thanks to CrusytCrab as well for the phone call. Will be defrosting my prawns and going to give Purigen a go

lol crusty is good for that now you'll have to owe him a pint, his is guinness

Nitrates are always hard to keep down.
The volume of water has to be taken into account.
My old 175Ltr tank was always up in the red for nitrates.
My 380ltr tank is in the yellow range for nitrates. The larger volume of water takes longer to be affected.
Regular water changes are the way to do it but to see a result the changes need to frequent and at least 30% of the water.
Saying that Nitrates are the least dangerous compared to Ammonia or Nitrite which should be kept at zero.
Unless you have very sensitive fish species most fish will tolerate high Nitrate readings.
How may tanks are out there with healthy fish and the keepers are not even looking at Nitrate readings or even doing regular water changes.
We as very responsible aquarists are unfortunately in the minority.

I'm told that the following product for the external fileter is very good at lowering Nitrates but i have never tried it.
www.aquarist-classifieds.co.uk/php/detail62_196759.php


Greg

In a fully mature tank, there should be few problems so long as the tank isn't chemically manky.

It takes at least 9 months to year for a tank to fully 'cycle' (and I hate that word).
It would be very rare for a tank to reach such a fuller nitrogen cycle in a shorter period due to the very very slow growth of aerobic bacteria that convert ammonia to nitrogen gas without going through the route of nitrites or nitrates.

90mg/l is really the max Nitrate level for tough freshwater species. And even then, chronic toxicity may show later in life (curled gills....unable to exchange gases effectively, and often seen in 'tough fish').

But, there is a risk that you don't end up catalysing the reduction of nitrates to ammonia.....if you have 50mg/l of nitrates that starts being reduced to ammonia then you are in trouble. This can happen in anaerobic conditions where hydrogen sulphide is being produced.

After many years of developing denitrification systems for marine keeping, I came to the conclusion 30 years ago that such system only address one problem with fish keeping, and that regular partial water changes are still vital as nitrates are not the only problem of a tank.

Often, with testing, one needs to ask if the test result is true or not.
There is no test kit that actually tests for nitrates......they are merely modified nitrite test kits.
It is very important to make sure that the reagents are used as directed and that phials are washed fully immediately after testing to prevent residual reagents and aquarium water affecting future test results.

ian

Thanks again all. I'm gonna try the daily water changes, clean the filters tomorrow and stick in some purigen to see if I can get the levels down a bit. Will let ye know how it goes. Have been doing large water changes for the last three days and no change from the bright red results so we'll see how it is in a week

Just a suggestion, but did you try doing a test on the water you are putting into the tank?It might tell you if the test kit you're using is accurate or not.

Stuart.

Yeah tested it at the weekend alright and got a zero reading. Thanks for suggestion though

Did you get a zero reading from the water straight out of your tap? if so,that changes things regarding the kit

ger310 wrote:

Did you get a zero reading from the water straight out of your tap? if so,that changes things regarding the kit

oh and not just your kit!!

Hey ger, i got a zero reading from the water i have ready for water changes - tap water in a bucket after being declorinated and after adding nutrafin biological supplement