Mini-cycle - What Should I Do?

[drewmac]

I started a 20gal planted tank 4 weeks ago. Started with 3 Tiger Barbs (before I learned about fishless cycling). Anyway, they made it through the cycling and last week I had readings of: Ammonia 0, Nitrite 0, and Nitrate 10. So I decided to add a few more fish, well actually a small Bristlenose Pleco and two African dwarf frogs. All seemed good for the first three days, readings remained at 0 with Nitrates at 10. Then suddenly I had a small spike in Ammonia (aprox 0.25) with still no Nitrite. I did a 25% water change at that time. The ammonia came down and then I saw a small spike in Nitrite. I checked the levels today and the ammonia is back up somewhere between 0.25 and .50 and the nitrite is back to 0 with the Nitrate close to 10. I am assuming this is a "mini-cycle" happening because of the new additions. Should I be doing water changes or should I be letting the tank adjust to the small increase in ammonia. I feel like I am ruining the cycle by doing water changes for small increases. The fish and frogs seem totally fine: eating normally, swimming around as usual.

Any advice? Basically, are water changes for small ammonia spikes a good idea while the tank is increasing its ability to handle increased bioload?

Anywa advice is appreciated!
Thanks!

 

[petertr]

Yep - keep up the daily water changes until the cycle is complete.

 

[drewmac]

So by doing daily water changes I won't be inhibiting the biological filter from building the bacteria required to break this ammonia down on its own?

 

[fatheadminnow]

So by doing daily water changes I won't be inhibiting the biological filter from building the bacteria required to break this ammonia down on its own?

When you do the water changes it will, yes, bring down ammonia which your beneficial bacteria need. But you will not be able to bring it to zero, no matter how hard you try. Eventually your beneficial bacteria are going to colonize enough, relative to how many fish you have in your tank. Say you do a 20% water change every day to keep it under control, then after a couple days, you might only need to do a 10% water change every day. Eventually it will be like every other day until you do not have to do them anymore.

Just try to keep the ammonia/nitrite under .25 ppm, and eventually it will all work out.

-FHM

 

[waterdrop]

Yes, that answer by fathead was so nicely worded I hesitate to add any more comments, but since I have a hard time shutting up I will anyway, .

Once you have fish, its time to never worry about whether your bacteria are getting enough ammonia (unless perhaps you are fish-in cycling a rather large tank with just a tiny fish or two, in which case you might want a fish or two more just so it wouldn't be so slow!) In most normal cases like yours there will be plenty of ammonia to develop the bacteria even when the test kit is measuring zero, just as said.

One comment I'd make is that your water changes seem too timid to me. If I saw a result like that .25 and then it even tried for .5 the next time, I'd have changed at least 50%, maybe even 70%, unless I knew there was a worry about my source water. If you use good water change technique, with 1x or 1.5x conditioning and rough temperature matching and the source water going in has zero ammonia and nitrates and the KH/pH difference is not enough to shock your fish, then good solid water changes are usually a good thing for both the fish and the developing autotrophic bacteria. The goal is to get ammonia and nitrite down so close to zero that the next reasonable time you're able to test and water change you find that it hasn't risen above 0.25ppm in either case.

~~waterdrop~~

 

[fatheadminnow]

Yes, that answer by fathead was so nicely worded I hesitate to add any more comments, but since I have a hard time shutting up I will anyway, .

~~waterdrop~~

LOL...

-FHM

 

[waterdrop]

Yes, that answer by fathead was so nicely worded I hesitate to add any more comments, but since I have a hard time shutting up I will anyway, .

~~waterdrop~~

LOL...

-FHM

I'm actually quite a good listener in conversation if you could know me in real life, lol. I hate it at fish conferences when you encounter hobbyists who only want to talk at you.

~wd~