Here I am again with a question about the equipment for the darkroom which I am putting together. I am only intersted in 35mm as of now.

I am now asking the following thing: would you buy a tank with room for two
spirals or for just one?

Basically, these are my basic doubts:

1. Would a single spiral tank allow to make higher dilutions?
2. How do I avoid waisting chemicals when using a bigger tank loaded with just one spiral (which will be the case most of the times)?

Following are the details of the offers from the online shop (price is pretty much the same):

Paterson 35mm Tank: 14xH12 cm (1 35mm spiral)
Paterson Universal Tank: 14xh17 cm (2 35mm spiral or 1 120 spiral).

Thanks for any advice you can give me