View Full Version : nitrogen cycle

03/24/2012, 11:57 AM
I've been checking the forums and haven't been able to get an answer for this...
If I slowly remove the bio balls from my wet/dry trickle filter, and replace them with LR...what happens to the first 3 parts of the nitrogen cycle? I understand that the ammonia - nitrite - nitrate conversions were happening with the oxygen-rich bio balls. The anerobic LR bacteria will work with the nitrate to nitrogen conversion....but what deals with the first 3 changes when the bio balls are history? Does my protein skimmer take care of them? And, if so, where does the nitrates for the LR conversion come from? I hope my question makes sense. I just want to get a good handle on things before I begin making changes on an otherwise happy 50 gal. reef tank. Thanks for the help.

03/24/2012, 12:26 PM
FIrst, It's the environment not the media. Live rock rubble in a wet and dry filter will be about the same as bioballs. It may catch more detritus and be worse overall, ime. Not much if any nitrate reduction will occur in the highly oxygenated water there. Large pieces of rock may be better but it's more a question of flow and oxygenation of the water in a trickle filter.
Second, As bioballs or other media are removed, ammonia oxidizing bacteria go with them. Slow removal allows time for an an uptick in other colonized areas of the tank( substrate, live rock,etc) to take up the slack without risking an ammonia spike.

03/24/2012, 01:16 PM
thanks for the reply tmz. So...in your opinion, I should leave the bio balls alone...or dump the whole trickle filter system? any suggestions will be appreciated

Randy Holmes-Farley
03/24/2012, 01:33 PM
The nitrogen cycle is easily taken care of on live rock, and there is no need for bioballs in a reef tank.

Do you have the rock in place now?

03/24/2012, 01:46 PM
the only LR is in the tank itself.

03/24/2012, 03:06 PM
I would personally remove the bioballs ,say 25% every 3 or 4 days. If you have adequate rock in the tank it should be just fine without them. If you need more rock and don't want it in the tank you could plumb in a moderate to low flow cryptic zone. I use a covered brute garbage can filled with larger pieces of live rock for example.. The water flows in slowly from the bottom and out the top.

Randy Holmes-Farley
03/24/2012, 05:43 PM
I agree. if the live rock is already there (which is good), just slowly remove the bioballs. :)

03/26/2012, 08:11 AM
thank you, tmz and randy for your kind help.

03/26/2012, 08:33 AM
You are welcome.