Internal worms

Question
I have a 44 gallon fresh water tank and several Balloon Mollies, a Gold Algae Eater, an Iridescent Shark, 2 Pink Zebra Danios a Cory catfish, 3 Scissortails, some Guppies and Swordtails. I have lost 3 fish in the last few days and some of my Mollies arent acting right. I have notices white stringy feces from many of my fish a long while back and bought some internal parasite medicine and it seemed to work (I have had to do this several times in the past few months). I have had my tank since before Christmas and have had nothing but trouble with it. My fish had Ick (which I treated) and bacterial infections (which I also treated)and internal worms (again, treated). My gold algae eater is covered with grayish-black spots and  a few of my mollies arent acting right and still have internal worms. I have been treating with Melafix and Fungus Cure all to no avail. My local aquarium store owner said they may be immune to the treatments since they have been treated so many times with the same things before. What can I do to get rid of these worms for good and get my algae eater better? BTW-I have had the alge eater for about 2 years (had it in my 10 gallon tank along with my cory catfish and the swordtails). I just had my water tested on Saturday and it was fine.

Answer
Hi Tina;

You might try feeding a medicated food. But first, fast them for four days. Withhold all food for four solid days. Your fish won't starve, it's actually healthy for them. White stringy feces can persist from an irritated digestive system after the worms/parasites are gone. A four day fast can help the digestive system rest and recover a bit before giving them the medicated food. External medicines often don't work because they don't get into the fish in a large enough concentration.

Keep the water and gravel very clean too. All tanks need a 25% water change every week along with a gravel vacuuming. Many times a well-meaning fish store will give you medicine to treat a disease that can be cured by just keeping a cleaner tank.

They tested the water and said it was "fine", but what does that really mean? Find out exactly what they tested for and what the levels were. They should give you actual numbers. It's easy to do a basic pH and even an ammonia test without finding anything remarkable. But, if they didn't check the nitrites or nitrates, part of the story is missing.

Mollies, guppies and other livebearers need very clean water to thrive. They start acting strange when weekly maintenance is not done or they don't get enough veggies. Give them cooked green beans, romaine, cooked and peeled peas, cucumber slices, squash slices. They can't thrive long term on a dry flake or pellet diet.

You should know too that irridescent sharks get to be over 3 feet long. He will soon get large enough to eat all your fish, especially at night. They are actually farmed in their native Thailand as food fish. It's a shame the fish store didn't tell you about all that. Here is a profile page about them;

http://www.aquariumsite.com/fish/siamese_shark.php

I hope everyone feels better soon...

At Your Service;
Chris Robbins