Water Change before first cycle

[fluke420]

I setup my 40gal 18 days ago. I have 2 silver dollars in the tank for 15, I know I should have done the fishless cycle. As of right now, there are no ammonina or nitrites at all. Is this normal? Is it wise to do a water change before the cycle is complete?

 

[JWright]

It's possible the spikes were so small that you didn't notice them. Two silver dollars aren't a huge bio-load for a 45.

I would say your tank is cycled if you have any nitrates.

Josh

 

[Matt Nace]

I agree..or the bio-load is so small that you didn't even reach an ammonia reading yet.

Like josh said, if nitrates are showing up(and ammonia/nitrItes are 0) you are cycled.

 

[colesea]

Just keep in mind that you are only cycled for two silver dollars. Any additional fish you place in this tank could very well off-set and recycle the tank again.  I usually do four fish every two weeks for a 40 gallon aquarium to makes sure I reduce the possiblity of ammonia spikes during the addion of new fish. It gives the bacteria a time to catch up with the additional bio-load. Just monitor your ammonia, nitrite, and nitrate levels. Heck, if you have excel, you can plot the values over the course of a week and actually see the process of the cycle in a graph.
~~Colesea