Fishless cycle

I've just read Diana's article about this.

Why the need to take out 80% of the water that you've spent weeks getting just right?

Well, the water isn't right at the end.

Think about it -

The bacteria have changed all the ammonia to nitrite - good

The bacteria have changed all the nitrite to nitrate - good

The nitrate is now really high - bad!!!

At the end of the cycle the nitrate levels will be about 80 or so, whereas you should never allow the to get above 30-40 maximum, and mostly it will be about 10-20 when the tank is up and running and you are doing weekly water changes.

So, you do your 80% weater change, get that number way down, and then keep it down by good weekly tank maintainence - water changes and gravel vac's

Oh, I see! Thanks for keeping me right! This is gonna be fun! I'm quite glad it's not just a case of popping a few fish in a tank and leaving them to it.

No probs mate. Listen, just nipping out for some petrol, then will be back to answer any other questions so have the ready

Great, thanks!

As Fishfan said, at the end of the fishless cycle, there will be a high level of nitrates so you do the 80% water change to remove them. This is also why you do weekly water changes of at least 25-30% to keep the nitrate level as low as possible.