my 40 barely fit under the 120's standard stand... we also braced the underside of the stands bottom to support the 40's weight ( it's runnign as a sump for the 120) on a 125 you'll have to do a custom stand 99% sure.. the 40 is as deep as the stand is. imo no safe way to do it w/out either building a custom.. or customizing a pre-fab stand quite abit.
Exactly custom stands are the way to go. I got $150 invested in this one. 125gal on top 40 breeder below.
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