Common seahorses generally do best at a temperature of 72–77 °F (22–25 °C), optimally 73–75 °F (23–24 °C). They do not tolerate even spikes above 80 °F (27 °C) well.[12] Their optimal pH range is around 8.1–8.4.[13] The common seahorse can tolerate a range of salinity from 18 parts per thousand (ppt) to 36 ppt but salinity below about 25ppt should be promptly corrected. About 32 ppt is ideal.[14]