Need Help With Fishless Cycle

[jason26]

Hey everyone, really need help with my fishless cycle. My 240 litre tank has now been cycling for 6 weeks,using sand as subtrate and have lots of rocks using a external fluval 405 filter, temp. is at 30 deg also have airstone inside. The bacteria is proccessing 4 ppm of ammonia within 12 hours, nitrite is off the chart and there is only 5 ppm of nitrate.

I did a large water change last week about 60% but i still dont seem to be getting anywhere.

Should my tank have been cycled by now and is there anything else i can do to speed things up.

 

[Gvilleguy]

Hi Jason, from what you are describing, your cycle is on track and just taking a long time. I don't know when your ammonia started dropping to zero, but the phase 2 where nitrite drops to zero can take upwards of twice as long as the ammonia phase. If ammonia is still processing to zero for you, then the cycle is working. Just have to wait for those N-Bacs to catch up with the A-Bacs.

 

[Bobtastic]

Yep... It sucks but there's not much you can do but be patient.

Well, there is something you can do and that is to get some donor media for a matured filter. Or some gravel from an mature filter which you can place in your filter and at a stretch some mulum (the dirt you clear out during a filter clean) from a mature filter.

If you add any of the about you'll introduce a portion of the required bacteria need for processing Ammonia and Nitrites.

 

[waterdrop]

Be sure your pH is up between 8.0 and 8.4 to help in the final stages. The larger amount of nitrate(NO3) being produced will increase the subset of nitric acid in there which will try to push pH downward unless you have a high carbonate hardness level. Both large gravel-clean-water-changes and/or baking soda can be used to adjust the bacterial growing soup.

There is nothing that says a fishless cycle will complete in 6 weeks and we've had them run beyond 100 days in a small number of cases but still ultimately complete just like all the others. It is likely there are still other factors about the water chemistry and growing conditions these bacteria like that we still do not know.

~~waterdrop~~

 

[jason26]

Thanks for the replies, tested again today ammonia 0, nitrite 0.5, nitrate over 160.

Cant beleive how much these results have changed over night, nearly there now.

 

[Skins]

Thanks for the replies, tested again today ammonia 0, nitrite 0.5, nitrate over 160.

Cant beleive how much these results have changed over night, nearly there now.

Looking good jason
Are you testing your parameters every 12hrs or once every 24hrs?

Keith.

 

[jason26]

Update everyone, nitrite finally went back to zero yesterday but still a little confused cus its taking over 12 hours to process 4ppm of ammonia into nitrite and nitrate.

Is this normal and would you say i am cycled or is it taking too long.

 

[waterdrop]

Right, what happens first after the end of the "nitrite spike" stage where nitrite just always measured very high on every test is that nitrite(NO2) will drop to zero ppm in -24- hours after ammonia was dosed. At this point you need to begin adding in a set of tests at the -12- hour (12 hours after ammonia was dosed to the tank) test. For instance, if you were testing and dosing at 7pm then you would now begin also testing (just testing, not dosing) at 7am. At first the amount of nitrite on the 12 hour test will be very high but eventually it will work its way towards 12 hours. Once you get the long sought after "double-zero" where both ammonia and nitrite are both zero ppm at only 12 hours after dosing 4-5ppm of ammonia then you are ready to start your "qualifying week." That just means you watch it for about a week and ensure that it keeps performing flawlessly.

~~waterdrop~~