I have a 75 gallon saltwater aquarium with the following:
20 - 30 pounds live sand
about 45 pounds live rock
1 peppermint shrimp
1 fire shrimp
2 yellow tail damsels
2 clowns
2 pj cardinals
1 yellow tang
1 conk
1 Halloween hermit
all are happy and alive with no noticeable issues. I have had this setup for about 10 months as a complete group but the tank has bee up and running for over a year and a half. I do have corals and they are all very healthy and actively growing. My problem is that every time for the last 6 months that I add a new fish with in 3 weeks to a month it dies. They all seem to have died the same why and very quickly. One day they are actively swimming and eating. Then they seem to all of a suddenly get lazy/lethargic. By this I mean they just hangout in the rocks or back of the tank. gill and moth actions seems elevated but not too they point that they seem stressed. Meaning they don't look as stressed as when you fist get them home after getting them from the fish store. Once this happens they are all dead within several hours. As this is happening all the other fish are acting normally. This seems to only happen in the late afternoon and they die over night. They will eat during this time but not very aggressively. I sometime find them after the hermits have gotten to them but the time I can get them out and look at them they all look normal. No spots cuts missing scales. I have gone through about 4-6 fish that all have died the same way. When this first started happening I would do a water test then a water change. All test where normal them so I thought I was testing wrong and now have the fish store run all my tests. They just tested and ammonia ph nitrate nitrite all normal. Calcium was a little low at 20 and alkalinity was low at 6. My alkalinity has always been low and I have always struggled to get it up and keep it up. I do not run a skimmer just because I have yet to find one that works. They just all seem to over flow and never make skimate. I know most of you will say that the canister filter is bad but I like it and clean it every 3 weeks. Other than not adding anymore fish does anyone have a thought on what might be happening. Thank you for your time and help.
20 - 30 pounds live sand
about 45 pounds live rock
1 peppermint shrimp
1 fire shrimp
2 yellow tail damsels
2 clowns
2 pj cardinals
1 yellow tang
1 conk
1 Halloween hermit
all are happy and alive with no noticeable issues. I have had this setup for about 10 months as a complete group but the tank has bee up and running for over a year and a half. I do have corals and they are all very healthy and actively growing. My problem is that every time for the last 6 months that I add a new fish with in 3 weeks to a month it dies. They all seem to have died the same why and very quickly. One day they are actively swimming and eating. Then they seem to all of a suddenly get lazy/lethargic. By this I mean they just hangout in the rocks or back of the tank. gill and moth actions seems elevated but not too they point that they seem stressed. Meaning they don't look as stressed as when you fist get them home after getting them from the fish store. Once this happens they are all dead within several hours. As this is happening all the other fish are acting normally. This seems to only happen in the late afternoon and they die over night. They will eat during this time but not very aggressively. I sometime find them after the hermits have gotten to them but the time I can get them out and look at them they all look normal. No spots cuts missing scales. I have gone through about 4-6 fish that all have died the same way. When this first started happening I would do a water test then a water change. All test where normal them so I thought I was testing wrong and now have the fish store run all my tests. They just tested and ammonia ph nitrate nitrite all normal. Calcium was a little low at 20 and alkalinity was low at 6. My alkalinity has always been low and I have always struggled to get it up and keep it up. I do not run a skimmer just because I have yet to find one that works. They just all seem to over flow and never make skimate. I know most of you will say that the canister filter is bad but I like it and clean it every 3 weeks. Other than not adding anymore fish does anyone have a thought on what might be happening. Thank you for your time and help.