Cycling question

[Amy T]

As some of you already know, I am trying to complete the nitrogen cycle in my already stocked 55g.  I did 6 days of Stability per the instructions on the bottle starting on July 14th (ammonia was 0.5ppm).  Ammonia is almost back to zero and on July 22nd the Nitrites started to increase (0.2, 0.5, 0.25).  I have been using Prime to detoxify the Nitrites for the past two days.
  
So my question is....I performed a 20% water change on July 13th and rinsed the canister filter on July 15th.  I am noticing a lot of fish poop in the substrate, but I am afraid to disturb the cycling process.  Should I do a gravel vacuuming now or wait until I see Nitrates?  Should I just do a water change without gravel vacuuming?  Should I gravel vacuum without removing water (with the Eheim gravel vac)?  I'm petrified that I will do something wrong and I'll have to start this whole process over again.  I've already lost a lot of fish and time doing things wrong:/

Thanks, guys!

Amy

[Carl]

Small water changes that include partial vacuumings is OK. This has been my experience.

As well here is a quote form the Nitrogen Cycle Article:
"Relatively new scientific evidence shows nitrifying bacteria to be sticky and adheres to the surfaces like glue (using exopolymeric substances), so agitation of filter media when rinsing (no tap water), or vacuuming of gravel will not destroy these colonies."

Reference:
www.americanaquariumproducts.com/Nitrogen_Cycle.html#biofilter

Carl

[devonjohnsgard]

If you have two forms of filtration, I would alternate cleaning between them. That way more good bacteria is developing. Clean one at a time.