brown turd on my gars, help me. please.

so not to long ago i noticed this sorta long turd like string on my 16 inch spotted gar named a cow ( because he is so fat and eats so much!). then i noticed that there were a few more on him like 3 of these brown turd like things. so i recorded a video and showed it to my LFS. they agreed with me that it did not look like a anchor worm because of the fact that it didn't split into two ends and didn't seem to be irritating the scales or a raised area. one more thing to note is that it doesnt seem to swim around in the fish it basically goes with the flow of the current. my LFS gave me two things to try out one was prezi or something like that, its on the safer side. and clout incase nothing seems to work i then just nuke the fudging thing. i don't want to use clout because it will be way to stressful on the fish. he still eats and swims around the tank. since i did the first treatment the brown turds have gotten smaller in size i have also been adding salt after every water change. however i just want to add i noticed two small turds on my skinny young gar named the punisher. very small though. just so you know they do eat. what they eat are tilapia and shrimp as well as krill. they will eat the crap out of krill but are picky about tilapia. there is also a silver arowana in the tank with no problems. he can almost eat a whole tilapia by himself.
what is wrong and what should i do!! i don't want to use clout if i don't have to!


you can see the brown string between the middle and end of video. keep your eyes above the fin towards the back.


link to video....

https://www.youtube.com/watch?v=6cF32ekNRvg&feature=youtu.be


thank you for viewing my blog hope this video is good enough to figure out the issue. sorry for spelling errors.

just to add on you can see the brown turd thing perfect around 30 - 33 seconds into the video. its actually in front of the fin near one of the spots. hope this helps finding it!

Bump

its the middle spot that looks faded sorta on the left side of it. look 32 seconds in and pause it there. i will try and get another video of it today.

actually even better view of it is at 26 seconds in. on the middle spot that looks faded. you will see this brown string that is drifting on the gar.

im going to be doing a new video today. i will do my best to get it focused on these little things. Thank you all for checking on it, appreciate the help!