Replacing Soil?

[theotheragentm]

I would assume that you would eventually have to replace soil in an aquarium after the nutrients are used up out of it. How often does this happen?

 

[joy13]

On one forum there is someone that has a friend that has had a tank up for something like 15 years. Mineralized soil substrate - Substrates - Aquatic Plant Central it is something I am thinking about for a 29 gallon planted tank. Right now I have tried some soil under fluorite with great results. There was a little more algae on startup but other than having to trim the plants every week it is great. They are 5 gallon tanks and I don't use any co2.