Aquarius 2-1/2-Gallon Aquarium Only $19 (reg. $33) The links in the post below may be affiliate links. Read the full disclosure Here.May 15, 2014 by SMFM Leave a Comment Â Amazon has the Aquarius 2-1/2-Gallon Aquarium Kit on sale for only $19.00 (reg. $32.99) with FREE Shipping via Amazon Prime or on orders over $35. Get this Deal Here!