Another Water Change?

[Gary D]

Hello,
We have just completed a fishless cycle in our 130 litre Aqua One 620T.
We have shown double zero's in 12 hours for the last seven consecutive days - yipppee

However, when I tested on Tuesday morning, the PH was starting to drop. It was about 7.0 whereas it is usually about 7.8. So I decided to do a 90% water change to be on the safe side.
I then re-dosed with ammonia, and sure enough, the tests were double zero again 12 hours later and the PH was back to normal.

We will not be adding fish until Friday this week, so I am going to continue dosing until the night before.
Firstly is this correct, or should I stop dosing 2 days before?
Secondly, and the main point of the question, is it necessary to do another water change so soon?

Thanks,
Gary.

 

[arobinson1984]

Hi,

I'd add the last dose of ammonia about 16-18 hours before adding fish to ensure it has all been processed, then yes do a large water change before adding fish to ensure nitrates are nice and low.


Andy

 

[waterdrop]

Yup, last dose the day before, although really there's plenty of flexibility as the colonies should be quite robust if they've passed the qualifying week. After the big water change be careful not to re-dose ammonia out of habit! And be sure to log the event in your aquarium notebook as this will mark the beginning of your first normal fish-in maintenance periods as far as water changes and filter cleans go.

Congrats Gary!

~~waterdrop~~