Brown blotches on powder blue

[tigerkayu]

Hi,

anybody with experience with powder blue tang. Mine develop brownish blotches on the skin after one week.

Mine is a fish only 6ft tank set up 1.5 month old. The PBT is about 5 - 6 inch, very aggressive, good appetite. When I bought it, the complexion was very pale blue, but very even. Now, the skin looks the equivalent of acne. It scratches occassionally, which I think added to the skin damage.

I'm stump whether its water quality problem, parasite problem or diet problem. Nitrite is low. Nitrate is low but rising (I think algae in sump have not taken off yet). I feed frozen & live brine shrimp, frozen mysis, flakes & seaweed. Lately, I've started soaking food in crushed garlic.

Help anybody?

[Achilles Tang]

From my experiences with Tangs,

I suggest you don't treat them at all... FW dips etc.

They are delicate creatures and stress kills them faster than ich will.

Try to provide a stressfree environment as best as you can for the PBT ie. no competitive/agressive tangs.

You want to make sure it's eating as much as it can.... so the best form of treatment is... making sure it eats quality food. Use food soaked with garlic juice. A compound in garlic causes ich to drop off their hosts.

Once its immune system is strong, it should overcome any further external parasitic attacks.

Good luck!

[tigerkayu]

Thks AT,

Do u advocate regular water change?

I thought the advantage of large systems is that there is less need for water change. Since my nitrates are rising, I have no choice but to do water change & large tank ( 6ft x 2 x 2.5)= large water changes!! But most books still recommend regular water changes regardless of tank size. Do u still need to do water changes if u manage to control nitrates with macroalgae in sump?

Do u also advocate lowering specific gravity to 1.017 to get rid of parasite?

[hotsoup]

I was informed that the Tang's family have some form of magetic field on their bodies causing them to scratch against objects. this may also be sign of "ich".