| Argulus are TERRIBLE! All kinds of small wounds that can lead to infections, etc. But, I'd guess the death was caused by the other parasites. Chilodonella and Costia can kill quickly. I've never had Argulus, but have seen them. Makes the skin crawl to look at them on a fish.
Your friend seems to have everything imaginable. (I think trichodina is about all he is missing!) A treatment plan is needed. Unless you can find a reliable source that dimilin can be used with Proform C, I'd not use it until other problems are under control. But, I defer to those more experienced in this sort of situation. ... If beginning treatment now, I'd do one treatment of ProformC, water change, then a treatment of Proform C and Prazi together (7 days), water change, then dimilin, water change and then a third treatment of ProformC. Without the argulus, I'd do the 3 consecutive ProformC treatments with Prazi in the last one. With so many parasites, some losses are likely inevitable. Again, I defer to those with experience dealing with all these critters at the same time! I've not had the 'pleasure' of the learning experience. |