Bacteria..?

[fishmad135]

My tanks been running for around 6 years, its not over stocked, and the last time fish were added was around 3 weeks ago..?

 

[waterdrop]

Tank size, num and sizes of fish? (gotta run, will chk bk later) WD

 

[fishmad135]

Tank size, num and sizes of fish? (gotta run, will chk bk later) WD

tank size: 60 litre
Number of fish: 4 guppies, 5 neon tetra (not fully grown - only about 1cm), 1 lone platy.. (its friend died a few weeks ago..

 

[waterdrop]

Nicely understocked - no problem with stocking I'd say. Nitrates are quite low (at 5 right?) So the only question here is why are we seeing a little ammonia above what the tap water is bringing in (ie. why has the biofilter not quickly eliminated that as it should) and similarly, why are we seeing any nitrite(NO2) showing up at all on the new API nitrite test?

When I see this in a 6yr old tank, the first things I think about are whether the gravel cleans and filter cleans are coming frequently enough or are thorough enough.. but the low nitrate is one clue that the maintenance habits may be pretty good (or it could be plants taking out nitrate?) Or I wonder whether the filter might be inexpensive or operating improperly and experiencing some "blow-by" where the incoming water that has ammonia and nitrite is able to bypass the media and bacterial action and get right back out in to the tank.

Anyway, I've tried to think out loud. I watch a lot of threads and make a lot of comments, but I'm just as limited as the next person in my individual ideas and diagnostics and there are probably dozens of members who comment here who are more experienced than me.

~~waterdrop~~

 

[fishmad135]

I just did a test on ammonia and i am happy to announce that the ammonia is 0, I probably put the spike down to my little sister feeding the fish a few days ago (as i wasnt around) and feeding them to much..

 

[fishmad135]

Nicely understocked - no problem with stocking I'd say. Nitrates are quite low (at 5 right?) So the only question here is why are we seeing a little ammonia above what the tap water is bringing in (ie. why has the biofilter not quickly eliminated that as it should) and similarly, why are we seeing any nitrite(NO2) showing up at all on the new API nitrite test?

When I see this in a 6yr old tank, the first things I think about are whether the gravel cleans and filter cleans are coming frequently enough or are thorough enough.. but the low nitrate is one clue that the maintenance habits may be pretty good (or it could be plants taking out nitrate?) Or I wonder whether the filter might be inexpensive or operating improperly and experiencing some "blow-by" where the incoming water that has ammonia and nitrite is able to bypass the media and bacterial action and get right back out in to the tank.

Anyway, I've tried to think out loud. I watch a lot of threads and make a lot of comments, but I'm just as limited as the next person in my individual ideas and diagnostics and there are probably dozens of members who comment here who are more experienced than me.

~~waterdrop~~

Thanks for the reply waterdrop

The substrate has been changed quite alot.. the last time i changed the substrate was about july 2010.. It is now sand, and i do a 15% waterchange everyweek or more if the tank looks like it needs it..

The filter is good and has a nice flow, only once has it got all bunged up and when that happened i must have spent a good hour or two taking the filter apart and unclogging it..

Lots of plants in there... i mean lots..

Todays test are
ammonia 0ppm
Nitrite 0ppm
Nitrate between 20 and 40ppm

Are these good results?

Yesterdays results were probably less reliable, First time i ever did a liquid test kit. And i know were i went wrong with the Nitrate result - I didnt shake the 2nd bottle of nitrate test solution before use for 30 seconds and i didnt shake the tube of solution for 1 minute after adding both test solutions.. But i have learnt from it, and wont do it again

 

[OldMan47]

The chemistry results that you posted, all zeros except nitrates, are fine. As far as using the nitrate test, double the times that are suggested and you will get more consistent results. The facts are simple, the 2 reagent test has a tendency to have the reagent precipitate and better mixing means far better, more consistent results. If your test kit is starting to get old, even banging the reagent bottle on a counter top can help you get better, more consistent, results.
If you results are consistently between 20 and 40 ppm of nitrate, try testing your tap water. A nice way to judge water changes is to change enough water that the tank water never exceeds the tap water by more than 20 ppm of nitrates. If your tap water shows zero nitrates, try a larger percentage with your regular water changes.
What we really use the nitrates to tell us is how much we have allowed impurities in our water to build before we do a water change. At around 20 ppm of increase, we are changing enough water to maintain all those things we cannot measure at reasonable levels. Our choices are to decide to try to measure all those things we cannot measure easily or to do large enough water changes to preclude much more of a build. At a 20 ppm nitrate build, the water will stay good enough for us in any parameter known to affect our fish.