I'd think that the extra water would dilute your ammonia levels a bit, but it doesn't sound like you're all that far into the cycle at this point...and you'll be glad to have the sump later as your tank matures -- i know adding a 10 gallon sump to my 20H has been a great change!
Good luck and let us know if there's anything else we can do to help.......
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20 High (started 5/18/06)
20 lbs live rock and 3" sand bed - Remora w/ MJ1200 & Prefilter - 10 gallon sump/fuge - MAG7 & SCWD return - 96w Nova Extreme T5's - Red-legged Hermits - Cerith Snails - Nassarius Snails - Royal Gramma - 6line Wrasse - Maroon Clown - Wheeler's Goby - Bubble-Tip Anemones - Green Star Polyps - Frilly Brown Mushroom - Green Bullseye Mushroom - Kenya Tree Coral - Xenia |