Fish have feelings, too! They may not be the smartest or most fun creatures, but how would you feel if you were locked in a room filled with moldy trash and hot, slimy dog poo?
I think that you should definitely offer to help clean the tank, and (like previously stated) you might even get the fish and/or tank for a lower price!
Hello; My take on this thread is that many of us who have kept fish for a long time think that fish deserve decent living conditions and that we would like to see the fish existing in bad conditions to somehow have their lives improved. The issue, to my mind, is that there are often restrictions on what we are able to do when poor conditions are encountered. In a fish store we can complain about the conditions and we can refuse to shop there. This may have some effect over time especially if they cannot stay in business.
In a private home the options are much more limited. The pet owner gets to run the tanks any way they wish and I do not know of any way to force them to do things in adifferent way. It is not that I want the fish to suffer, but that I have seen this sort of episode play out several times over five decades. I have seen tanks be abandoned to a fate of no care untill the water evaporated and the fish were all dead. A few people have called me and asked if I could take their fish. I took in a common pleco when some neighbors lost their house a while back. It took over a year for me to find a suitable home for it as it was outgrowing my available tanks.
I have offered to take the fish from people who were clearly no longer willing to do the caretaking and had those people refuse the offer. Some sort of denial of the conditions in the tanks. In the end the tanks wound up sitting in storage after the fish were all dead. I have known of people who just killed all the fish and took the tanks down. This at least was quick.
The situation described in this thread is unlikely to have a good outcome. It appears that the owner does not have consideration for the poor conditions in which the fish in question are suffering. I would like to have worked out some sort of tactic for addressing this type of situation by now, but have not. Some decide to get out of the hobby and try to find a good home for their remaining fish. Others just stop taking care of their tanks and allow the fish to slowly die and cannot be reasoned with. I no longer encourage people to get into the hobby as I have seen too many give it up after a couple of years and often the outcome is not good.
