Fish not pooping

[DougA]

Hi,

I have a new 20G freshwater tank with 7 Cherry Barbs. The fish have been in the tank for 16 days, and I have not yet noticed any pooping or evidence of poop. Is this a problem that I should be concerned with?

Some facts:

1. pH ~ 7.2. It was slightly higher at one point and I brought it down with API pH Down.

2. Ammonia 0 ppm

3. Nitrite 0 ppm

4. Nitrate ~3 ppm

5. I am using the API Freshwater Master Test Kit

6. Feeding - for the first 12 days I feed Aqueon Tropical Flakes. For the past few days I rotated in Cobalt Tropical Granular, and Omega One freeze dried Brine Shrimp. I feed once a day, and I'm confident I am not overfeeding.

7. I ran the tank for several days prior to adding fish. I conditioned the water in advance.

8. The fish behavior seems good. They are active, chasing each other, swim in all areas of the tank, color is good, bodies look good, and they eat when fed.

9. The tank has not yet cycled. I test daily and have never had any Ammonia reading above 0 ppm.

The only problem I've had is a lack of pooping, unless the failure to begin a cycle can be considered a problem.

I would appreciate your advice.

Thanks.