trace element top-up question....
 

I was wondering. I have an 18 gallon reservoir for water top-up in my 90 gallon tank. It's gravity fed with a float valve. I want to put some of my trace elements like iodine, vitamins and stuff in my reservoir so I'm not putting it in manually weekly into my sump. Is there a formula/equation or easy way of figuring out how much of the stuff to put into the reservoir so that I get the right amount of "stuff" in my main tank? I probably have to fill my reservoir up every 3 weeks to a month.. My gut instinc tells me just to put about 3 weeks worth of vitamins and iodine in every time I fill my reservoir...does that make sense?

trace element top-up question....
 

Personally I don't add any trace elements at all. With regular water changes you shouldn't need to do this at all. Everything you should require is in there. What are you keeping in yoru tank that you feel requires you to add these elements?

As for vitamins. What are you adding? Selcon? Vita-chem?