fish that can't tolerate hyposalinity?

[snorvich]

Oh, and by the way, when you use hypo, what SG do you use? My recollection is that it must be exactly 1.009

 

[LukFox]

I used exactly 1.009~.

 

[jmaneyapanda]

Make no mistake, hypo has negative effects on ALL marine fish. Just some not as severe as others. And, we, as aquarists, tradeoff the potential negative of hypo vs the perceived positive of parasite control. I, like Snorvich stated, feel people use their "quarantine" tanks, as "treatment" tanks. I, personally, do not believe in prophylactic treatment, particularly in cases of extremity. Qt should be synonomous with a period of observation, of suitable duration. Ick, as an example "disease", does have measurable symptoms, or tests which can be used to determine its presence.

 

[snorvich]

Make no mistake, hypo has negative effects on ALL marine fish. Just some not as severe as others. And, we, as aquarists, tradeoff the potential negative of hypo vs the perceived positive of parasite control. I, like Snorvich stated, feel people use their "quarantine" tanks, as "treatment" tanks. I, personally, do not believe in prophylactic treatment, particularly in cases of extremity. Qt should be synonomous with a period of observation, of suitable duration. Ick, as an example "disease", does have measurable symptoms, or tests which can be used to determine its presence.

This reflects my viewpoint as well.

 

[LukFox]

Ick, as an example "disease", does have measurable symptoms, or tests which can be used to determine its presence.

Like that? If you don't see a spot on the fish for 8 weeks, do you just assume you would have seen one in that time period if it had ich?

It's just I was reading this last night in another thread, and I'm not sure a normal quarantine length is really enough to be certain you'd see a spot.

As has already been mentioned here a few times, the parasites CANNOT go dormant. It always goes through the stages. However, in fish that have been exposed to the parasite previously and developed immunity, only a few parasites are hosted. On average, the number is only in the teens or single digits (depending on the level of initial exposure), whereas an otherwise healthy fish with no immunity hosts about 330 on average. When you consider that >90% of the external surface area of a fish is in the gills, that means that in most cases when the parasite load is low, chances are good that none of the parasites will settle where you can see them. Even in the case that one does settle where you can see the nodule, chances of one spot going unnoticed are still pretty good. If you have 13 parasites on the fish (the average # from BM95 for fish with low-level immunity), one will only settle where you can see it about every 3rd cycle and 2 will settle where you can see them about every 4 cycles on average. If you have 7 parasites (the average for moderate immunity) the odds of having 2 where you can see them drop to about 1/8.

So.. are there other symptoms? What if there is no scratching because the parasite load is so small? I'd say most tanks have at least a small load of ich parasites, but people don't see the fish scratching all of the time. Just curious if there's another way that doesn't require actually seeing the spots or scratching. Interested in what tests there are especially.

 

[Chris27]

i have heard to treat puffers with hypo and NOT copper

Given that puffers regulate osmolarity with their skin more then other fish, I don't know why you would want to stress them even more with Hypo?