I Need Help...ASAP please!

[Angelfish Fonzie]

I recently bought a driftwood, and a couple of Anacharis, an anubia, and a java fern. After I installed everything properly.. a week later, one of my 3 year old Angelfish started acting strange..
Now my Angelfish swims at the bottom of the tank, on one side.. barely moves, but he still eats. He just recently pooped out a long string, white string with a small red tiny dot like the regular color of poop, on the tip of the string.
My pleco also pooped out a looooooong transparent string almost right after the angelfish, but he looks fine to me...
I've been researching online and it says it might be parasites...but how? I've had these guys for 3, almost 4 years now.. parasites now? or is the fish stress? Please help, and thanks for reading.

 

[Kevin8888]

your wood or your new fish could have introduced parasites. Or they could have had them for a long time and only gotten worse more recently.

 

[purplecandle]

It is not uncommon for a pleco to poop a transparent poop, I call it a casing, like an empty sausage casing.

Could be internal parasites- Stress from the new environment may have weakened the fish and allowed a parasite infestation

Or it could be constipation, constipation can create white feces.
here is an article on that http://www.fishchannel.com/fish-health/disease-prevention/fish-constipation-food.aspx

Are there any other symptoms? What are your water parameters?

 

[Chaz88]

Could have brought something in with the plants or wood, that was dormant before encountering a favorable environment and host fish. Would be one of my first guesses if everything was alright for a long time before the change.