Aquarium Cycling

Question
I am new to the hobby so some background.

I set up a new 30 gallon freshwater tank on Dec. 25. I added tap water, installed all equipment and let tank
'run' for 24 hours. Decorations are plastic plants, pirate ship and long air stone. Filter is an AquaClear 70
which is rated for tank sizes 50-70 gallons. I bought the tank used and thought it was 40 gallons which is
why I bought the bigger filter.

On Dec. 26 I added 3 goldfish from a small 6-10 gallon tank. I used the tank water as well as the
filter media from the small goldfish tank to facilitate cycling.

I've tested the water every day since then and all levels remain consistent. PH is stable at 7.8-8.0, ammonia
and nitrite are at zero and nitrate has been about 0.25-0.5. Temperature has also stayed consistent at about
74 degrees. The goldfish are feeding and seem happy.

Ammonia level never went above zero and the tank never became cloudy.

My son wants to add guppies next. My question... is it too soon to add more fish? I know its only been a week
and most people say cycling could take up to 8 weeks. I'm just wondering if the ammonia level will eventually
go up, then come down, OR, is it stable because I started with established water(about 6-10 gallons) and
filter media.

Also, would 5 guppies be too many to add right away or should I only add 2 or 3? I figure if the breed is a
schooling fish, I should add the minimum amount for 'schooling'.


Answer
Hi Doug,
 You can probably add the 5 or 6 guppies.  Just be sure not to feed them too much and do not let uneaten food sit in the tank, i.e., feed them once a day and only what they eat right away.  It will take about 6 weeks for the tank to fully cycle but adding the existing water has probably helped the process go smoother.

-- Ron C.
  rcoleman@cichlidresearch.com
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