Yellow Tang suffering from lateral line erosion.

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Aquarium Advice Apprentice
Aug 10, 2003
Silver Spring, MD
Well, this is a sort of two fold question, it has become apparent that my Yellow Tang is suffering from HLLR. It has two white spotches on either side of his body, his color has faded and his top fin has cuts in it. And I also believe that the cause of this is the fact that I've been very busy and my younger sister has been doing the feeding for the part month or two. She feeds them all just Marine flakes, clownfish, tangs all alike, nothing but marine flakes. Well I took some initiative a few weeks ago and changed things around.
Instead of using chemically treated tap water for water changes, I decided to go the extra step and now I purchase gallons of distlled water from the supermarket, about 20 gallons at a time, usually costs me about 12 dollars and I just add salt, mix, let the power head run through it for the whole day and add it into the tank at night. Well this has sort of cured my red slime algae problem that I had, but I still have two problems.
These little white dots appear on the underside of LR, filters, and the back of the aquarium. I was told these are sort of tiny worms that live in these little shells, but they're kinda getting out of hand. Also, I only had a red slime algae problem previously, which is gone, but now I have this hair algae problem which has now shown it's face. I tested the water and Ph is perfect, ammonia, nitrates and nitrites are 0. Salinity, well it's a little more than it should be, around 1.027 but I usually add a bottle of fresh water every now and then to get it under control.
My question is, is it ok to use distilled water? I'd rather not make a purcahse of a RO Unit, much happier spending 14 dollars every two weeks.
And ideas on the algae problem?
For some reason every time I move the LR around while gravel cleaning, these little transparent bodies of really tiny looking shrimp float around. They look like discarded shells, is this something I should be worried about?
PS. The tank is a 50 gallon. With not enough LR, I know, about 30 lbs of LR.
Fish. 2.5" Yellow Tang. 2" royal grama
1" yellow tailed blue damsel, 1.5" true percula clown, 1.5" tomato clown, 1" pink skunk clown.

I used to have a carpenter flasher wrasse, but the poor guy kicked the bucket once. He was fine in the morning, swimming around as usual, came back from work that evening and the guy took a permanent time out and was lying on the bottom of the tank, stiff as he was dead. :(
1. HLLR can be caused by several different things, diet being the primary cause. A proper diet with vitamins should clear it up in time, but my tang didn’t recover from HLLR until I put a grounding probe on my tank. Some will disagree with the use of a grounding probe, but I’m certain that’s what cured my tang.

2. Distilled water is fine to use, but you can purchase a good RO unit for less than $100 (I paid $69 for mine) and in the long run it is far more cost effective than buying your water.

3. I wouldn’t be concerned about the dots or the empty shells unless they take over the tank. I'm not real sure what it is your seeing, but the addition of another fish/invert that eats the critters may be in order. If they are pods then its a sign that things in your tank are going well.

4. I would slowly start removing water from the tank and replacing it with fresh. Over the course of a week or so get the salinity down to a comfortable level and then try to maintain that level. Fluctuations in salinity or temperature cause stress.

If you want to see what kind of "shells" they are, click on the link in my signature, then go to the "educational" section...scroll down to "Common Critters." You'll find it there.
can anyone tell me what's HLLR? I just got my yellow tang 1 week ago and it's starting to have the same problem as Infinity. ty
The common name is Lateral line disease. Short version is a lack of color and a lateral line that runs down the mid part of the body of the fish. Its normally due to a poor diet. Never purchase a Tang that has a discolored lateral line down its body. It takes some TLC to get them past it.

I noticed on your reply you mentioned a grounding probe. I was just wondering about extra electrical voltage in my display tank. I've never tested for it but I recently read that it is a more common problem than people think. I was wondering if you could tell a little more about testing for it and where you got this grounding probe. I'm not much of an electrician so its all greek to me.

That's it EXACTLY. Thousands of them. Well...maybe not exactly thousands, but a whole lot.
And the little shrimp guys which seem to be occasionally camping out in my filters or under LR look like this.
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