CLEAR gnat larvae in RV Grey tank!! how does that happen?

RV TANK LEAKING, looked like the water was moving, looked closer and hundreds of CLEAR THIN WORMS. What the heck are they!!(they're that larvae)

[EdYochim]

Cool. My cat was hiss and scratch carpet And pounce on carpet dad look ! I peeled carpet to find strange pebble looking things also look like candy tiny and many colors, shapes and sizes. They slowly move and they have a head and 2 eyes as well. Str8 up i burned a few with torch they glowed red and turned into a charcol. Unfortutunitly they did nit die. They gather in pairs even group of 20 i put in same container and tried drown the mfers, water made them stronger and i could clearly see a
it ws growing fast and was over 3 ft long 2 arms with round head and the most evil creepy look on its face as i ran with it in a pot, to the river beside my rv site . This is alien parasites that i had under my carpet. This happened todsyv