[ODDBALL361]

I have a Yellow Tang that has red patches on it they are on both sides near the tail fin. Can anyone tell me what this is??

[BubbaWPB]

an infection of some sort (bacterial or protozoan)... Chuck, Ninong, greenbean and a few others have some good links to identify fish diseases (and treatment for such)... I can't seem to find them right now.

[Steven Pro]

Yellow tangs are particularly prone to develop red blotches when water quality dips. Low pH or alkalinity or high nitrates or dissolved organics can cause this.

[ODDBALL361]

I do water changes once a week. I missed one week. I had a spike in ammonia and nitrite but it was a small rise ammonia 0.25 same for nitrite. Nitrate was normal at 20 thats as low as it has been since I started the tank will this cause the condition on the Tang. and if so will increasing water changes clear this up or do I have to buy some kind of meds and QT the tang??

[BubbaWPB]

Disease and Disorders of Tropical Marine Fish

Hopefully, it's just red blotches from water quality... you can have a look here to see if it might be something more serious.

[ODDBALL361]

Thanks for the reply. This site is fantastic. I will keep an eye on the Tang to see if it improves any if not I will QT it or should I QT it now. Will this spread to my other fish if its kept in the display tank??

[BubbaWPB]

If it is just stress, it wouldn't necessarily be contageous... if it is bacterial or parasitic, it could. All depends on the cause. Did you see anything that looks like it on the disease page? ...or better yet, do you have pics?

[Mini_Reef]

by any chance do these "red blotches" look kinda like fish bite marks?
I have a yellow tang also, and he's got some red-ish spots around
his eyes/face. I know my nitrates are a bit high, somehow I had too many fish in my little 30 gal, but i've got a handle on things again.
How long would it take to clear up with good water changes and proper conditions?

[ODDBALL361]

Thanks for all the reply's Tang is back to normal. I did 2 water changes over the weekend and the red spots have disappeared. Now I know I can't miss any water changes. Thanks again for a great resource of information!!!!

[sahmad43]

what size tank you have and how much of live rock ? also what kind of filteration system you are using?
try to find out the spikes you getting in amonia and nitrites and eliminate that instead of doing more than one water changes in a week.

[ODDBALL361]

I only do 1 water change a week I missed one and that is what caused the spike. Tank is 75 gallons only 30 Lbs of live rock right now, will be adding 45 more Lbs in a month or two. My water parameters are
Ammonia=0 ppm
Nitrites=0 ppm
Salinty= 1.024
Nitrates=20
Ph=8.2
This is as of last night 5/1/06

[vtec si]

I have a few questions for you oddball. Do have a skimmer? Are you running carbon? If no you may want to look into these things. On a 75 gallon tank, you should be able to get away with a water change biweekly. Also your nitrates are still high.

Good luck,
Martin

[ODDBALL361]

Yes I have a Remora C Pro skimmer. I use a Fluval 404 with carbon in 2 of the trays. Took out the Bio filtration. My Nitrates have always been 20 since day one of set up. I don't know if it could be my well water or something else. I can not afford an RO filter for my water yet. Any suggestions on another way to bring down my Nitrates would be appreciated. The fish seem to be fine the way the tank is they are active and are eating.
Yellow Tang
Volitan Lionfish
Yellowtail Damsel
Maroon Clown