Do pressure tanks need to be identical in size when daisy chaining multiples together?

No.

Explain "daisy chain"! Are they in series or parallel? jlisenbe nailed it. The tanks can be different sizes.
Why are you doing this? Regards, Tom

Explain "daisy chain"! Are they in series or parallel? jlisenbe nailed it. The tanks can be different sizes.
Why are you doing this? Regards, Tom

I currently only have a small tank that the draw down point is at 5 gallons because I jumped the pressure from 30/50 to 40/60. I thought it would be a good idea to add another tank so that the pump does not come on so often. What do you think?

I would do it, but you might just want to buy a larger tank and use it by itself. Having longer pump cycles is a good idea.

Are we talking pressure or bladder tanks? Let me know, Tom

SB, that is a terrific question. If they are the old galvanized tanks, then it would be much more difficult to do what he is describing.

You said you had a small tank, so I took that to be a bladder tank.