i have a 15 with about that much now! lol but seriously the only thing that you really have to worry about is the space for the fish and the placement of corals. i have had to say no to some corals because the rock frag was to large. but seriously you should be fine with that amount of rock in the tank!
i have not had any negative effects except that i think the nitrates are storing in my rock, but that is just a theory and my nitrates stay at about 5 to 10. so im not to worried about it.
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15 gallon aga
20 pounds lr
35 pounds ls
Current Power quad 96 watt retrofit
ZooMed Powersweep 214
Aquaclear 70 moded into refugium
two trumpet corals (1 light blue, 1 lime green)
star pollyps (pink base with yellow tips, and regular green)
various mushrooms (over 5 types)
metalic green frogspawn
sea mat (aka button polyps)
2 false percs
1 cherub angel (2 1/2 years old)
2 blue legged hermits
2 turbos
2 margarita snails
2 Astrea snails
| 
30 lbs fiji rock in a 20 Gal 
