Ya, Think of an RO
unit as an investment vs a purchase. At .60 per gal
lets say ou do a very conserviitve water change every month of 20%. Thats almost $65/year spent in buying water.
That does not sound to bad but should you upgrade your tank at some pont your water usage will go up and so will the cost per month of the water. Plus you have the time and effort of lugging 9 or 10 gal
water home each month and mixing it with saltwater.
I have not even talked about dailly/bi-daily topoffs from evaporation. Les say you get 1 gal
a week in evaporation (again very consevitive) thats an additional $28/year in replacing evaproation.
So in a years time you would have spent over $90 on water. And when your done using that water it goes down the drain so its like just giving the money away where as with the RO
unit you can produce your own water on demand.