Dear R2R Friends, i have mixed reef (SPS, LPS, ZOA...) i have noticed several of my SPS quick growing such as: Digitata and Montipora and some other SPS, grow quickly but skeleton is very fragile. if i to compare same type of corals i brought from store which are more thick and strong. what should i do to make them stronger and less fragile ? Thank you all !! Nimrod _________________________________________________ I dose: Cal, KH, MG: Depend on consuming. Calc powder. Two Little Fishies Amino Acids, TropicMarine ProCoral Mineral as mention on directions. I Use: No water changes regulary. carbon as mention on directions. Red Sea Coral Pro Salt. my parameters are: 700 Liters two+ years (grow up from 400L for 4 years same stones and sand most corals are new). Salitiny 1.025 KH - 9 Royal Nature Test Cal 420 Royal Nature Test Mg 1320 RedSea Test Phospate: 0.12 hanna Temp 25-26 PH: 7.9 (night) -.8.3 (day) LED lights: 2 X 200W Zetlight 6600. Ozonizer as mention on directions. Protein Skimmer Deltec 702.