[CollegeReefer]

Alright, let see if we can give you a hand. Lossing fish is never a good thing and loosing fish multiple times is even worse. I will first like to say that i doubt it is the water you were using or the water clairifier. But we will need some more information first.

You said that your tank has been set up 3 months, how long did you cycle your tank for? How long after that did you had your clean up crew (CUC) and how long after that did you indroduce your first fish? What fish did you add first? How long after your first set deaths did you had the new fish? Once again what fish did you add and when. One those fish died how long did you wait after that and once again what order did you put the fish in? This will help in indentify possible causes.

What do you keep your saltinity at? What do you use to check it. What have your ammonia, nitrates and nitrites been at? What is your temp at? Does your temp change alot or is it constant? These few things can tell a lot about your tank.

It is my guess that it has too do with your water chemestry and the stress of your fish. Damsels are really aggrisive and though small will pick on all of the other fish especially if they were introduced first. I always stear new hobbiest away from damsels. Your Salifin Tang needs to be in at least a 125 gallon tank. Haveing a stressed out fish can cause many problem in a tank and when i fish is in too small of a tank that causes stress.

You said your water was cloudy which is never a good sign. With such a small tank and no protein skimmer i would be doing bi-weekly 20% water changes. With your live rock, your canister filter isn't really doing much by the way.

The last thing i would like to point out is that your fish dieing is most likely your fault. Some neglect on your behalf most likely caused your tank to crash 3 times. I am not trying to sound mean, but when you loose all fish, you don't just add new ones, you need to figure out what you did. Seeing that you addid three sets of fish in the last 3 months shows me that you have not taken the time to learn why. Even if it did have to do with the water you were using, after the first time you lost a fish, you would have figured that out. Also seeing that you had a tang that needs a 125 gallon tank in your 45 gallon tank show me that you have done very little reading on your fish before adding them. How much reading have you done on this hobby?

Once we figure out exactly what caused your tank to crash, i will strongly recommend that you do not add any more fish to the tank for a while. use this time to read up on fish you would like to keep and find out what their needs are. I hope you don't take what i said as mean, but it does sadden me and others on this forum that so many fish have died in your tank.