Does the 10% sea water replacement each week include the sump volume?

[markjd]

As I'm a newb, I have a newb question: does the 10% sea water replacement each week include the sump volume? So for my currently planned 20G main tank, do I include the additional 10G of the sump for the weekly sea water replacement? If true, that would mean 2G versus 3G sea water replacement. I know it's not a huge amount of difference, just wondering.

 

 

Mark

[LiQuiD]

Yes, it would include the sump. The 10% is just a rule of thumb that has done well for many (myself included). But it will depend on your systems factors (type of salt, type of water, amount of inhabitants, length of time the tank has been running, etc.) You could end up doing 10% every 2 weeks or 20% a week. Start with the 10% rule then adjust to your specific tanks needs (you will figure those needs out as time goes by.