However, the hobby’s current favorite corals, the chalice, lords, scolies, and LPS in general come from deeper and more sheltered environments. These habitats experience much cooler temperatures on average, lower flow, and much less temperature fluctuation than the shallow water SPS corals.
So this brings us back to the titular question, how hot is too hot for a reef tank? If my experience and observations can be a guideline, you really should aim for
77F for a mixed reef – if you have more LPS corals knock that down to 75F for a bigger buffer against rising temperatures, and if your reef is focused on SPS, let it ride at 79F and don’t sweat it.
Since we’re in the middle of the summer, it’s no surprise that temperatures are rising for everyone in the northern hemisphere, and the tanks that live there. It’s about this time of year that we get…
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