On the other hand - if specific toxins are a general problem - 10 % weekly WC in an aquarium like mine will not change anything. It will only take a little longer time before it is a problem. If I was concerned of this - I would prefer a 70 - 80 % WC each year or so. I´m not against WC - if needed. But I do not think regular, small WC will change anything. Because I use a type of Balling (Triton Core 7) - my salinity rise and I normally need to take out around 4-6 litres of water each 14 days in order to maintain a salinity around 35 psu. It means - reality - that I do a 1 % WC a week.I'm personally not so much worried about TOC when using organic export methods of various sorts, as opposed to smaller amounts of specific toxins, of which marine organisms make a lot.
My aquarium 5 years ago
and today
As you can see - there is a lot of corals known for chemical warfare in this tank (and has been here for more than 5 years) - I have never been out for an event there I suspected toxins from the corals as a cause. I´m not so voried about this. I use an oxidator and it can be the reason why I don't get toxic levels of these toxins.
Sincerely Lasse