Hyposalinity treatment in my dispay tank

[ayrton]

Hi Leebca, I had talked to you previously about an ich outbreak in my 550 gls FWLR display and in particular about one of mine two clown triggers whose gills are heavily infested.
To cut a long story short my clown trigger is ok now in my qt tank and its gills are normal without using any anthibiotic.
But in my display tank, where water salinity is 12 ppt (sg 1.009), all my fishes, after 3 weeks of hyposalinity, show white spots that are very very little (in their dimension). I don't Know why these little spots are still present on my fishes? ; My refractometer is ATC and I've calibrated it with distilled water. It show my salinity at 12 ppt!!!!!!!
Do I need wait a few minutes after placing some drops of salt water on it to obtain the correct reading? What is minum salinity that fishes are able to support?
Thanks for your answer!

Lorenzo

[leebca]

Hi Lorenzo. WELCOME TO REEFLAND.

I remember your fishes. A refractometer reading is instant. You put the drop on and flip the cover over it and it is ready to read.

Fish have been known to tolerate very low salinity (for instance, they can stay in a freshwater dip for 30 or more minutes). Long range studies haven't gone much beyond a salinity of 14ppt. However, during the treatment of Marine Ich (Cryptocaryon irritans) a salinity of 11ppt is fine for several weeks.

Hyposalinity is really only effective against Marine Ich. If your fish have Marine Ich then there should be no visible spots after a maximum of 3 weeks. There are very few exceptions to this general statement.

Marine ich is very white in color and has the size of about a grain of salt. That should still be a good measurement for you there in Italy. Are you sure it is Marine Ich? I think at the outset I mentioned that a proper diagnosis is very important. At that time you were sure it was Marine Ich so you proceeded to treat for Marine Ich. Are you still sure it is Marine Ich?

If you are unsure, I will need to see a photo of what you are seeing, or you will have to do some investigation into what they could be. If you want, you can answer some questions about what you are seeing, but the best thing would be for me to actually see the fish with these on it.

Are the spots very small? Are they the size of talc powder? Does the skin of fish have a sheen to it from these spots? Is the fish flashing (scratching)?

Are the spots under the skin? under the mucous layer? on top of the mucous layer (if you can tell)? Any other symptom or condition the fish has?

Have you been watching the pH and water quality during your treatment?

That's all I can think of at this time to ask. A photo would be most helpful.

[ayrton]

These are photos of some of my fishes; it's very difficult to see these very tiny spots that are on their body; they are like dust but I don't think these are Amyloodinium ocellatum...I hope so
Some fishes is scratching on the sand. They look like cryptocarion but my salinity is 12 ppt by one month.
What do you think about these?

Lorenzo

[leebca]

I see white 'spots' in the photos even where there is no fish. So, I'm not sure how many of the ones I see on the body (behind the head) are real or just a spot on the photo.

If you're referring to those spots on the faces of the fish, then I think if you look closely they are not raised spots. They are in fact holes or pits. Is this not true?

You are also correct in saying they are not the size of typical Marine Ich.

Please look closely and see if you see that the spots are pits/holes and not raised up. Thanks! ;)

[ayrton]

Hi Lee, they have on their bodies many little spots that are raised spots but it's not easy or possible to see by photos; I can see, as I said before, when I look the fish in front of it, against light, white spots that are very very little (in their dimension). It's Crypto in my opinion but I don't know why these little spots are still present on my fishes with a salinity of 12 ppt.
Is it should be amyloodinium..... how could I treat it with copper in my display tank...I can't put my 230 kg of live rocks anywhere and it' s the same for my sand...this nightmare won't stop ever!!!!!!!!!!!!!!!!!!
Please help me Lee!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Lorenzo

[leebca]

Lorenzo,

I'm convinced it is not Marine Velvet (Amyloodinium ocellatum). This disease kills within a couple of days and hyposalinity has no affect on the disease organism. So, seeing that your fish are still alive this long eliminates Marine Velvet as a possible diagnosis, in my opinion.

I'm not convinced the face spots are Marine Ich (Cryptocaryon irritans). Those on the face look like they are pits in the photo. They look more like Hole in the Head Disease, or HLLE.

These are very important questions Lorenzo. Please think about this before you answer. Do the spots disappear and then show up in other areas or do they remain in the pretty much the same place all the time? If you took us a current photo of the same fish, would the spots still be there in about the same place?

In addition to answering the above questions, it is time to gather more information. I want you to catch one of the worst infected fishes and give it a freshwater bath/dip.

I understand that catching the fish won't be easy, but you just have to do it. For help on catching the fish, see this post:
How to Catch Fish -or- Goin' Fisin'

I want you to follow this process for giving the fish the freshwater dip:
Freshwater Dip for Marine Fishes

Can you gather up the equipment and things you need for the freshwater dip? Follow the above instructions.

After the dip, (this is very important Lorenzo) I want you to look closely at the bath water and see if you see anything that came off the fish. Then I want you to look closely at the fish and see if it has changed in appearance any.

If you can't answer the above questions or perform a freshwater dip/bath on one of your fish, then there isn't much more I can do. If the freshwater dip/bath doesn't work, I'm going to ask you to perform another dip treatment on the fish, so don't return the fish to your display. Once you've caught the fish and given it the freshwater dip/bath, then I want you to put it into a quarantine tank (and not return it to your display tank).

Good luck!