Ceylon's and F-8's?

I haven't, and probably would not. Figure 8s do not need high brackish, and only get to ~3". Ceylons get to >6-8" at least, and like GSPs, need to move up in specific gravity as they mature - up to full or near-SW. Although Ceylons are considered milder than GSPs, they get awfully big to be w/F8s.
 
My F8s are at around 1.008-10, my Ceylon is at 1.021-3.
 
It takes about a cup of salt/5gal to raise the SG .005. You'll have to do the math.
 
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