In my opinion its just about efficiency verses contingency. Running individual set ups increases the cost considerably since there is so much stuff to buy that you could leverage between the two. Of course that depends on whether you have equipment that is rated for the additional water volume. Having them all on the same system leverages your initial investment and probably decreases maintenance but if you ever want to isolate something or treat something etc you dont have a separate system to do this in... This is at least what I thought of when planning my frag tank add on. I am planning on linking into my main system since in my case I think the economic benefit outweighs the contingency.
|