i dont have a HUGE tank but i can tell you that the work involved w/maintaining a large tank takes a new form... ( this is the reason why you see a bunch of good-high end equipment used on large tanks, it helps w/ maintience )... i only have a 155 w/ a 55 as a sump/fuge.. with only actually 125gals of water in the system at any given time... it takes time just to get the ro/di ( about 6 hours) then to mix salt.. about 30-40 mins before i can dump it in the tank... so thats a decent amount of time compared to lets say a 75 gal when the whole thing may only take 1 hour to harvest and 15 mins to mix the new SW.... this is only WC ...imagine having to test the water, clean skimmer, break down equipment and clean them, adjust water chem... and so on...
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