shrimp?

Question
Hello! i was hoping you could help me, i bought a cleaner shrimp about a month ago, the first 2 weeks he was cleaning my fish and now he has seemd to stop cleaning them! although he is doing fine, is there something i should know.........one more thing he is missing pieces of his antennas will they grow back? and could it have been caused by a bad mold? thank you.....ps how should i go about changing the water in my tank??should i make the new water salinity the same as the one in my tank before adding it in?????????thank you!

Answer
Hi there, He should be fine if he is acting normally other than cleaning the fish. His missing bit should grow back. By "mold" I assume you mean Algae and if you have a lot of this then you may need to check your water parameters (nitrite, nitrate and ammonia) as algae feeds off excess nutrients. I would also keep the lights on only 6 hours a day until this clears. To change the water you will need to go to a fish store and buy a gravel cleaner. Ask them to show you how to use it correctly. You then drain about 10-15 of the water as you clean the gravel. Top it back up with salt water.
Hope this helps.