Longest Possible Safe FW Dip?

[rayjay]

Dipping the tank will only be temporary relief for it as the ich is in the tank.
He has an outbreak now due to the stress of being moved to your tank, and possibly due also to trying to establish a territory that others are not willing to give up on.
I would redo the reefscape so that they ALL have to re-establish their territory at the same time, making it easier for it to settle in.
If ich gets to be quite bad you may have to give it a dip just to give it more time to get established, but removing it to dip it is a big stressor in itself.

[TimT]

Since the tang is already in the Display tank my suggestion would be to get a UV sterilizer. Powder type tangs tend to be ick magnets... any temperature fluctuations and they get a few spots. I think a UV would do the tank well and would keep ick from overwhelming the fish.

[rayjay]

UV normally only works part of the time and is a big expense that IMO, isn't worth the money.
The problem being not all of the parasitic stages of the ich go through the UV and the fish, remaining stressed, still presents visible signs of the ich.
You DO however, lower the level of inherent zooplankton that the corals feed on as some of it goes through the UV and is killed off along with the portion of parasites that are killed.
IMO the best answer is STILL to remove the source of the stress.

[TimT]

In an ideal world it is best to try and remove the stress on a fish. It may not however be possible as it could be a health issue with the fish. The fish go through a lot stress and handling from Reef to Retail.

In the real world the Ick doesnt care if the fish is stressed or not. A fishes immune system is so compromised by the time a hobbyist sees it that providing a stress free environment wont help it much. A good analogy is to compare Ick to a mosquito. Eating a healthy diet and living stress free won't stop you from being bitten if mosquitoes are around. There are people who are mosquito magnets while others hardly get bit. I seem to be the magnet type. LoL

In a Display Tank UV works well when properly set up... flow rate and wattage. A lot of times people don't set it up properly so it does next to nothing and they figure UV doesn't work. For a 200 gallon tank I would recommend a 50 to 60watt UV with a pump that does about 500gph. I setup a Coralife Turbo Twist 36 watt with a Maxijet 1200 on a 150 gallon tank and it cleared up the ick in no time. Cost was about $250.

There is only one life stage that Ick and Velvet can be destroyed and that is the free swimming stage when they are trying to find a new host. Most tanks don't produce a lot of zooplankton so I would not risk your fish for it. Chances are most zooplankton larvae is from pods or bristle worms anyways.

Cheers,
Tim

[AquaticFinatic]

thanks timt for the advice. great info