They dont have LR
or invertebrates, usually because copper is used in the system, and they wouldnt be able to survive . As for the fish, the idea is to bring in fish that the store knows will sell quickly. Sometimes mistakes are made and fish that wont sell, or are priced to high may have to stay longer than expected. Some of these fish will get sick because they arent fed correctly, or are beat on by other fish, or are in the wrong type of water conditions. Some of them will hang on until they are finally sold, the others will waste awy until they finally pass away. Unfortunately the collecting and selling of the sea life is a big business, and with the quckness that the business must run, some losses are expected.