Freshwater Ich's Tolerance to Marine Salt

Hi all!

I got a Figure 8 Puffer a couple weeks ago, and like most brackish fish, he was purchased in freshwater. Despite that, he's perfectly healthy, and is actually much braver than my Green Spotted Puffer, at least when it comes to interacting with me. A very fun fish!

He's living in a 36 gallon bowfront tank that I've planted with salt-tolerant plants (Java Fern, Anacharis, Cryptocorynes, Marimo, Java Moss, Anubias), and is so far pretty relaxed with tank mates. I put a small guppy in the tank 4 days ago, and he's yet to bother it - so tonight, I'm adding a trio of platies. If the pairing doesn't work out, I can move the platies to another tank, but from what I've read, they should be fine together.

I've read a few different sites now, and have come across information stating that it can handle anywhere from 2-5 PPT (1.0015-1.004 SG), and was wondering if anyone has experience with this specifically. I know that usually salt isn't a recommended treatment for ich, BUT for fish with a high salt tolerance (like the platies) or brackish fish (like the puffer), is it viable? Does it work?

Here's one of my sources, if anyone's interested: CIR920/FA006: Ichthyophthirius multifiliis (White Spot) Infections in Fish

 

I have no personal experience but according to this experiment (on Mollies) it worked even better than the traditional formalin-malachite green combination:

(PDF) Efficacy of sea salt, metronidazole and formalinmalachite green baths in treating Ichthyophthirius multfiliis infections of mollies (Poecilia sphenops)

It seems that the dose was 10g/L. I'm not sure if even salt tolerant plants could handle that?

 

I have no personal experience but according to this experiment (on Mollies) it worked even better than the traditional formalin-malachite green combination:

(PDF) Efficacy of sea salt, metronidazole and formalinmalachite green baths in treating Ichthyophthirius multfiliis infections of mollies (Poecilia sphenops)

It seems that the dose was 10g/L. I'm not sure if even salt tolerant plants could handle that?

This is a good read, thank you!

If I'm correct, 10g/L is about 1.010 - right? I'm not familiar with "g/L", and I'm not sure if the calculator I used is correct.

No salt tolerant plants could handle 1.010, other than Mangroves, Marimo, and maybe a couple species of marine seagrass, to my knowledge.

So now we know that 1.010 will definitely take care of ich - I assumed that a SG that high would, but now we know for sure.

I've seen it recommended that 1 tbsp of salt per 2 gallons of water will kill most strains of ich - that'll work out to 1.0016 SG, if my math is right. That'd support the info I found on the other site.

My goal for this tank is 1.004 or so - I plan to let it swing between 1.002-1.005, as the fish and plants in this tank should handle that range quite well, IME. I'd imagine that 1.004 (which is a bit over double the recommended 1 tbsp per 2 gallons) would do the job.

That said, that recommendation is if you're using aquarium salt, and I understand that aquarium salt and marine salt aren't the same. Is it likely that they'd have a similar effect on a parasite?

Thanks for any information!

 

Considering marine salt is almost 90% NaCl, I think you can treat it almost the same. I'm sure you can find plenty of records of people treating ich with the equivalent of 1.001~1.002, so I wouldn't worry about it in 1.004.

 

Sounds good! I raised it to 1.001 tonight, and will raise it by .001 daily to 1.004.

 

I'm purely a freshwater hobbyist so can't help much further I just recalled previously reading that experiment and thought it might help. I think you're right, the general recommendation seems to be 1 tbsp/2 gal (I think 1 tbsp = about 15 grams) though they often come with a proviso that if not effective an increased concentration may be required. It's possible that you could consider it generally sufficient as a preventative. A higher concentration might be advised for treating an advanced or heavy infestation.

 

I'm purely a freshwater hobbyist so can't help much further I just recalled previously reading that experiment and thought it might help. I think you're right, the general recommendation seems to be 1 tbsp/2 gal (I think 1 tbsp = about 15 grams) though they often come with a proviso that if not effective an increased concentration may be required. It's possible that you could consider it generally sufficient as a preventative. A higher concentration might be advised for treating an advanced or heavy infestation.

I appreciate it. The puffer is the only one exhibiting symptoms, and he's only got 4-5 spots over his body. I'm sure there's more in his gills, but he's behaving normally, so I'd call it a minor case. Hopefully the salt is sufficient! If not, I can order some Ich-X. No biggie.

 

Sounds good! I raised it to 1.001 tonight, and will raise it by .001 daily to 1.004.

If your tank is cycled as freshwater, I'd recommend only raising it by .002 per week for a smooth transition/acclimation of the BB, it's said that more than that can cause your cycle to crash.

 

If your tank is cycled as freshwater, I'd recommend only raising it by .002 per week for a smooth transition/acclimation of the BB, it's said that more than that can cause your cycle to crash.

Thanks for the concern!

That said, I've raised and lowered salinity faster than .001 per day before without issue. I wouldn't necessarily recommend it to anyone else, and if I were going much higher than 1.004 I'd take my time, but it should be fine. I'll test for ammonia and nitrite, just in case.

 

I decided to keep the tank at 1.002 for a couple days out of curiosity - is 1.002 enough to kill the ich?

I think it is. It's been about 3 days since I spotted the ich, and as you'd expect, most of the spots have disappeared off of the puffer, with no new ones appearing. It hasn't spread to the platies either. So, I'll hold it here for another 3-4 days, just to see how they fare.

 

One of the platies came down with a bunch of spots today - going to add enough salt to take the tank to 1.003.

 

Tank has been at 1.003 for a couple days now - the tank stocking is now as follows:

1 F8 Puffer
3 Platies
3 Balloon Mollies
3 Guppies
15-20 Ghost Shrimp (snacks)

The puffer and platies are now clear of ich, and the guppies have never shown symptoms. One of the mollies has a single spot on his tails, but the other two are clear. However, that spot wasn't there yesterday (as far as I could tell), so I'd still consider this an "active" infection.

Could this be a salt-tolerant strain of ich? Ich's life cycle takes roughly 3 days - it's been above 1.002 (the SG where ich SHOULD die) for longer than that, and the tank has been "brackish" for 6 days - the same length of time as the study that was linked above (although this is at a much, much lower sg). That said, some people say salt can take up to 10 days to kill ich, so maybe I just haven't left it long enough.

Just updating this for Google - maybe someone else will have the same question!

 

No spots today that I can see, however two of the mollies are white, so they may just be hard to see. Fish are all behaving normally, and I haven't seen any flashing in 3-4 days.

 

Still no spots. It's been 8 days, and I haven't seen an ich spot in 48 hours. I think we're good!