When only 1 fish shows Ich, will a Fresh Water Dip help cure them?


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Sorry if I am asking a repeat question here but after 2 hours or research I could not find any comments on this.
About 2 weeks ago I added a Blue Tang to my 70 gallon corner tank. I didnt want to add him b/c I knew they were more prone to parasites but my wife HAD to have Dorie. Its a FOWLV, PH 8.3, Ammonia, Nitrite & Nitrate at 0, salinity at 1.025.
Dorie brought Ich into the tank. My Flame Angel got a spot or two but it went away after a few days. All other fish look great, everyone is eating fine including Dorie, but tonight the spots look worse than before and she is scratching quite a bit. I don't have a quarantine tank and I dont want to add copper to the tank either. Considering all the other fish are doing fine, I was thinking of a fresh water dip for Dorie but I could not find any comments on this forum about the subject. Will it help, is this a wate of time? Any thoughts or opinions would be appreciated. Thanks in advance.
BTW, I just added a UV Steralizer today so I am hoping if I can get Dorie cured the tank should be good.
You need to treat every fish in your tank to get rid of ich. You then need to leave the tank fishless for at least 8 weeks. This is because there are a different life stages of the parasite. Only one of which is visible on fish.
I wouldn't do a fresh water dip. It will only kill the parasites on the outside of the fish and stress the fish completely out. Possibly killing the fish

Please read the stickie at the top of the Disease forum

Also, a 70 gallon tank is not big enough for a Dorie :( They need tons of room to swim and most likely will be constantly stressed and sickly. I know it is hard, but sometimes you need to tell your wife that you can't have a certain fish because it isn't compattable.
Big ol' +1 to BJ.

If she really wants a Dory, you're going to need a much bigger tank. Not down the road, NOW.

That fish will be miserable until the day it dies. Not really thinking about the animal in this situation. These animals are removed from the ocean... we need to think about their quality of life above our own wants and needs.
Your tank is 1/3rd the size it needs to be for that fish, so it will always be battling ich, stress, HLLE or some other form of sickness.

To treat for ich you need a hospital tank, and you have to leave the display fish less for at lest 8 weeks. Then you need to QT anything that goes in the tank afterwards, or you are right back where you started. A freshwater dip is terrible for the fish, and any ich it kills will be replaced when you put it back into your tank
Man, you guys are tough. According to Blue Zoo Aquatics, the minimum tank size for an adult Dorie is 75 gallon. My tank is a 70 gallon (only off by 5 gallons) and Dorie is a juvenile less than 2 inches. There is plenty of swimming room in the tank, especially when you consider the fish store keeps them in 10 gallon tanks (if that) for weeks on end. So, its not like I threw caution to the wind, I researched and thought my tank would be suitable for at least 1-2 years until I either upgrade or find her a new home.
I read the "Oww No I have Ich" article along with Copper 101 and several others, but again, I don't have a quarantine tank and purchasing one and quarantining ALL my fish for 8 weeks with a zillion water changes etc. seems like major overkill considering only ONE fish is sick. I seriously doubt the LFS will allow me to return a sick fish, so unless I add copper to my display tank putting all my healthy fish at risk, I am kinda out of options.
With more research, you would have found that the tank sizes on Blue Zoo are way, way off. Live aquaria is a much better resource. You'll see 180 gallons listed there. They need a minimum of six feet of swimming space- 8 feet is better. There are days where mine looks cramped in my 180 and it isn't even close to full grown. We aren't telling you this to ruin your day, we want your fish to be happy and for your tank to be successful.
Also, just because only one fish is exhibiting the signs of ich, doesn't mean the others don't have it. In fact, it I can almost guarantee that they do have ich. It is just that their immune systems aren't compromised and are able to fight it off. Think of it like the common cold. We all have it all the time. It just takes us getting stressed and bam, we get sick. If you were to just treat your blue tang, then as soon as you add it back into your tank, then it will contract it again.

Also, these people here aren't harsh. They are actually tame compared to other forums when someone puts a fish in a tank that isn't compatible with it.
Hey guys,
I sincerely appreciate the input. Again, it was not like I was just putting in any fish I wanted, I researched and found it compatible with the fish I already had, and thought it was appropriately sized for my tank, according to Blue Zoo anyway. (I guess I wont use them for a reference anymore.)
So all the fish have Ich in the main tank (like people and the common cold) but all appear to be doing fine. I do not take cold medicine unless I "feel sick." So why treat ALL the fish in the tank when only ONE is sick? It just does not make sense to me.
So if I purchase a quarantine tank and treat Dorie with the Hyposalinity method, should I simply try and return her to the LFS after treatment? Do you feel all my fish will start to exhibit signs of Ich in the days or weeks to come if I do not treat them?
Again, thanks in advance for the input.
BTW, stock list- Juvenile Lion FIsh, 2 clowns, Flame Angel, Long Nose Hawk Fish, Dorie, and a Coral Banded Shrimp.
Chances are that they will not develope ich, however, it will still be in your tank. The key would then to keep stress levels down by feeding quality food, doing water changes to keep the water quality up, and keeping your tank stocked on the low end to avoid territorial fights.

Also, thanks for asking BEFORE dosing copper. It will kill your shrimp, and I also believe that the lion fish is susceptible to copper based treatments. It would also kill any corals you have in your tank and prevent you from having any in the future since it will be absorbed in your rocks.
Not just one fish is sick. Your entire tank has ich. Every fish has it. Not every fish may be showing symptoms -- but unless you treat all the fish, odds are they will get outbreaks on and off forever. And for sensitive fish (like tangs) these outbreaks are enough to kill them.

So you can just treat the one fish that shows symptoms, but as soon as you put it back in the tank with the other fish that are carrying ich, they will give the ich right back to the tang, then it will have another full blown outbreak.

Think of it like HIV/AIDS. I can have HIV/AIDS and show no symptoms. You would never know. I appear and act perfectly healthy. We have unprotected sex, and BAM, you're now infected. People that aren't showing signs of the disease will still pass it on. If you want to eradicate HIV/AIDS, you have to get rid of it in everyone, not just the people that are sick from it. Because the people that carry the disease and are not sick from it are the ones that are spreading it to everyone else.

It is pointless to simply treat the one fish that is showing signs of the disease. Because the other fish that aren't showing symptoms will just give the disease right back to it once you put it in the tank with them. Then it will get ich spots all over again.