Saltwater tank i need answers !!!!!

[housebuster]

saltwater fish onlt tank 72 gallon, on end of cycle 6th week. temp 77 and amonia and nitrites are at o level. why are all fish dying except the cleaner shrimp ? just did a 40gal water change and added a tomato clown and two blue damsels ,one and a half days later two damsels dead and clown hovering near the top of tnk. cleaner doing ok i used too much prime maybe before he 40 gal change ? and i used nitro max to help cycle the tank faster. i think i used too much of that also but not sure why fishes are not making it when all my water tested are good ?what do you think????

 

[tjm80]

What test kits are you using?

 

[carey]

You might wanna stop adding fish until you finish your cycle.

What are your nitrate levels?
Salinity?

 

[thominil]

There are a number of factors that could be causing this. More than likely, it is related to the water parameters. I recommend that you take all fish/inverts back to the store and read up on fishless cycling. Stop adding so many chemicals and additives since they just make you tank unstable. Rule of thumb is to not add anything that you can't test for. As tjm is getting at, post what your kits are, test strips are unreliable. Please post your water parameters each time you have a problem in your tank. Tap water could also be a factor here.