Rate of salt removal....

[cohazard]

Why salt works, in this instance, is because chloride is lethal to the free swimming stage of Ichthyophthiriasis (Ich).

Osmoregulation in bony freshwater fishes is largely a function of the chloride cells (as well as accessory cells), located on the gills. Freshwater bony fishes (guppies, rainbow trout and tilapia, in particular) have been shown to actually increase or decrease the number of chloride cells and accessory cells present in the gills when moved between freshwater and saltwater, and vice versa. This adaptation takes only 24-48 hours.

I'm less familiar with the function of chloride cell adaptation in marine bony fishes.

In my own experience in aquaria, I've found no advantage (measured in mortalities) to slowly adding 2 tbsp/gallon of table salt over a 24 hour period or adding it all within an hour when treating batches of fathead minnows (to be used as feeders) in multiple trials.

That's some good info there Ras......I've been wanting to feed live feeders, and now I know that I can treat them all at one time without killing them....

 

[tbone-ike]

Is it possible to test the salinity level when using table salt?

I've been treating for ich for a few weeks, and plan to discontinue salt addition at my next water change.

My concern: I'm getting some brown algae and plan to buy some ottos and I know they don't like salt; I just don't know how many water changes (or how much) it will take to get salt levels down enough to be otto friendly.

 

[OrionGirl]

Yep--but you'll most likely need a refractometer. Swing arm hydromters are often inaccurate at the lower levels of salinity. Wouldn't hurt to try it--but keep in mind that the dosage level used is below normal brackish conditions. (~1.005)