My stand is builded with 2x6's, with no center brace I have a 150 gal tank 48L x 30W x24H sitting on it, with a 50 gal sump 48L x 12W x 19H. I double up the 2x6's for the posts and have and a 2x6 horizontally, sitting on top on one of the 2x6 post. I also made the side panel removeable so that the sump can be side in or out.
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Attachment 3824