Lobsters And Algae Killer

[lostcrow]

Hello All,

I'm fairly new to the keeping of aquariums and have had a 30 gallon for about three months with 2 blue lobsters, 3 Columbian Tetras...and formerly a Blue Convict. Generally, the lobsters ignore each other unless them happen to meet; the tetras hang out in the middle and ignore the lobsters and vice versa; and the Convict was a very curious and happy fish that pretty much ignored the tetras but would occassionally 'sniff' at the lobsters. He was very quick, but very curious, and one day I found him dead with a small hole eaten in him (very sad, he was an awesome fish). I've read the posts about keeping fish and lobsters together, and watched them carefully after putting them together and they seemed fine - but I know that 'resting' time is the big conern. Well, I thought it was curious that the lobsters didn't consume the whole Convict. About a week later the tetras started acting funny - not feeding, swimming little and twitching while sitting still. Then I noticed a brown spot on the glass that resembles a filamentous fungus (my grad degree is in microbiology) so I bought some algae killer on recommendation of a LFS owner. He was aware of my collection and said nothing of possible implications on my lobsters but when I arrived home and read the bottle it said that it was not to be used with invertebrates like snails and such. I put ~half the recommended dose in after a water change and scrubbing the spot off the glass (considered taking it to the lab and culturing it for identification).

I apologize for the long intro, but here are my questions:
-Is it possible the Convict was sickened by the fungi and then grabbed?
-Does anyone have experience with killing fungi in the presence of lobsters?

Thanks

Greg

 

[Redbled]

Hey Greg,

I'm not sure about fungus, but I know I've treated my tank for parasites with my crayfish in it. I rarely use chemicals in my tanks anymore, just 50 percent water changes, however I'm not sure if that would help you or not.

 

[lostcrow]

Thanks for your reply Rebled...since, as you can see, you are the only one who has replied. Glad I didn't wait around for anyway to save my lobsters...

Actually I did my own research and what I found is below in case anyone else has lobsters with a fungal infection.

Apparently the reason for not using 'algae killers' with lobsters is their low tolerance of copper (copper sulphate is one of the actives in these products), which is 74.4ug/g in tissue and 0.5mg/L in water. The copper effects the stretch receptor that is used to locate food, and causes a latency (blindness) or even aversion when locating food if critical limits of copper are approached (Sherba et al., Ecotox. Envir. Saf., 2000, 329). The effect is reversible if removed from the copper-tainted water. You can also treat your lobsters for copper toxicity with copper chelators such as EDTA (typically used as an anticoagulant) or penicillamine (Tan & Roth, Neuropharm., 1984, 683).

What I found when I calculated the concentration recommended on the product is that the concentration was still below that found to be toxic in lobsters, but removed them to a hospital tank prior to treating anyway.

Greg

I'm not sure about fungus, but I know I've treated my tank for parasites with my crayfish in it. I rarely use chemicals in my tanks anymore, just 50 percent water changes, however I'm not sure if that would help you or not.

 

[big mick]

My lobster is kept in a tank on her own and have never needed to treat it for anything. Your lobsters are preditors so there is every chance it was them that killed the fish but you'd be best to test the water stats and post them.

.....as for "(copper sulphate is one of the actives in these products), which is 74.4ug/g in tissue and 0.5mg/L in water. The copper effects the stretch receptor that is used to locate food, and causes a latency (blindness) or even aversion when locating food if critical limits of copper are approached (Sherba et al., Ecotox. Envir. Saf., 2000, 329). The effect is reversible if removed from the copper-tainted water. You can also treat your lobsters for copper toxicity with copper chelators such as EDTA (typically used as an anticoagulant) or penicillamine (Tan & Roth, Neuropharm., 1984, 683)."

.......you what? heh heh heh!