My cardinal has this weird stringy poo ( picture ) .He stopped eating yesterday, I am scared if it is an internal parasite that more fish can have it in my tank. Should I dose some prazipro into the tank??? Or just take him out to QT? Thank you.
Best to remove the fish and treat in a QT where you feed medicated food directly to the fish's gut.
Or you can feed it in the display - carefully. Small amounts so the fish eats it all/almost all. Use a turkey baster to remove the uneaten mix.
Food + General Cure (1 scoop) + Focus (1 scoop) + a small pinch of epsom salt + a bit of water to the consistency you want to work with.
For the food I usually take 6-8 frozen fish cubes place them into a bowl in the fridge to "slump." Mix the food and then strain off the excess liquid (it will spike your nitrates + phosphates).