when you say large tank what are you implying?
Like a 90 gal
? Or a 45 gal
This is what I do.
I have two 30 gal
trashcans. 1 is for freshwater storage and the other is for saltwater mixing. I mix saltwater in batches of 20-25 gal
. I have a heater and powerhead in the trashcan. I mix at laeast 1 day in advance but usualy i have saltwater made up.
The 'lazy' way is to get a large pump and hose and pump the water from the storage container into the tank once the dirty water has been removed. Else you just use 5 gal
buckets and scoop out water from the trashcan and into the tank once the ditry water has been removed.
Doing a 10% water change biweekly is not going to take you more than 10-15min even on a 90 gal
tank. Its two 5 gal
buckets out and two 5 gal