Thanks a lot Jimmy for the info, I will be visiting Home Depot for the material during the long weekend.
Thanks Mark. The tank was setup about 2.5 years ago. One mistake I made to start with was I put in too many rocks/SPS at the beginning, and could not stop adding more along the way (talking about this addiction). As a result, I have to keep on pruning the SPS to keep them from touching/killing. I eventually get tired of doing it and stopped prunning, and many corals grow into each other with some small amount of dying off at the touch points. A little more than a year ago, many SPS grow to the water surface and filled the top portion of the tank. Due to the large quantity of SPS, my jetstream1 calcium reactor and PM kalk reactor could not keep up the calcium (calcium had been around 360 for more than half a year), this together with blocked lighting/flow due to SPS, bad reef crystal salt, and possibly stale topoff water, the SPS went on a long dying off period where I lost many of the large colonies (honestly, I am not sure the exact reasons). Earlier this year, I tore off most of remaining large colonies and started from small frags again (all corals in my tank started from 1" frag except the hammerhead), and it finally swing everything back to balance. But now my tank is overfilled with frags again. I do not want to replace the setup, but am worried that it might repeat what happened in the past. Recently, I bought a used cube setup, and I will set it up next to the current tank. This way, I can have both top down view on the cube and the side view on the current tank, and hopefully this will take care of my overcrowding problem, at least for a short while

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