Help!

[*blacksnapemoor*]

I HAVE A BLACKMOOR AND A ORANDA IN A TANK both of them have been pooing long white poo now my blackmoor has a lilttle white blob on the end of his tale i havent a clue what it is should i take him out incase my oranda gets it plzzzzzzzz help i am gonna do a 20 - 30% water change in a min please help whatt should i do?

 

[*blacksnapemoor*]

 

[WILDER]

Need more info.
Size of tank in gallons or litres.
Water stats in ammonia,nitrite,nitrate, and ph.
Can't make much out in the pics can you describe the white blob in more detail.