Changing Out the Filter in a Newly Cycled Tank

[Twoapennything]

First of all, thank you to everyone for tolerating my incessant questions - I really appreciate it.

Some of you might remember my post a few weeks back about my Penguin 100 filter that just stopped working for no apparent reason. Well, today I exchanged the Penguin for an Aqua ClearPower
Filter (the box says "Formerly AquaClear 150"). Thing is, the tank is newly cycled and has perfect readings with ammonia, nitrites, and nitrates all at zero and a pH of 7.6-7.8.

If I replace the filter, will I totally decimate the tank's biological well being? Right now I have a crappy Tetra filter going - it's the one that came with the tank kit and I consider it my back up filter.

How should I handle this? How can I change out the filters without destroying the good bacteria balance? I read that most of the good bacteria lives in the filter, so I'm worried. I could seed the tank with the filter from the Tetra if that would help. Any advice is welcome. Thanks!

ETA: I forgot to mention that this is a 10 gallon tank.

 

[spoonman]

I would first question that the tank is cycled if you have 0 nitrAtes. I would run both filters for a couple of weeks then remove the old one. If you dont have room for both take the media out of the old one and stuff it in the new one.

 

[dkpate]

+1 for Spoonman

 

[mgamer20o0]

well the way i read it took the old one off put the new one on. i would watch the tank since you will most likely have a mini cycle to say the least.

 

[Twoapennything]

I would first question that the tank is cycled if you have 0 nitrAtes.

Thanks, Spoonman, and everyone else for the advice.

Regarding nitrates, should I just wait? Because the tank did go through a good nitrate spike that lasted about a week. What level of nitrates would indicate a fully cycled tank?

I went ahead and switched the filter out and put the filter bag from the Tetra between the carbon and the pellets in the AquaClear.

Here's my API colors:

 

[Aquarium1]

a fully cycled tank usually has about 5-15ppm of Nitrates.

 

[Twoapennything]

a fully cycled tank usually has about 5-15ppm of Nitrates.

So, should I just keeping testing daily (I have been) and wait for nitrates to rise? I'm hoping at least that the 0 levels of ammonia and nitrites are a good thing . . . yes?

 

[Aquarium1]

Maybe you didn't shake the nitrate bottle enough. I did that when I first got my kit and it gave false readings. You have to shake the second bottle for about 2 minutes and the tube for another minute or 2, if I can remember correctly lol. Although you might hav done that, just checking. and yeah, 0 ammonia and 0 nitrites is good.

 

[mgamer20o0]

if you are doing many large water changes with low bio load you could get that reading also if you have a good amount of fast growing plants.

 

[7Enigma]

Something very wrong with your results. NitrAtes of 0 are pretty much impossible in your tank since you don't appear to have any live plants and have it stocked to an adequate level. As mentioned the nitrAte AP test is the easiest one to get false results. You need to follow the directions exactly. Shake bottle 2 for a minute or 2 vigorously prior to doing the test (this bottle is full of crystals as it's a saturated solution), then after adding the 10 drops cap and shake vigorously for a FULL minute. Failure to properly perform this test will give you completely false results. I'm hoping with your stocking you will see closer to 10-20ppm (depending on when you did your last water change and %).

Regardless, add the new filter to the 10 gallon and leave the old filter on there for a month or 2.