male guppie

Question
Hi!
My male guppy has been very sluggish.  I notied a black spot on his body near his fin.  He seems sick.  Does this sound like a disease or just old age?  I have had him for only about 6 months.

Answer
Hi Mark;

Without knowing anything about your tank and your other fish I really can't say if it's from disease or not. Sometimes a black spot can indicate waste toxin burns but sometimes it can simply be a color change. Or, possibly cancer. You might have the water tested for the levels of ammonia, nitrite and pH to see if anything is wrong there. I would go ahead and make a 25% water change and see if he perks up. Guppies and other live bearing fish really need very clean water to thrive long term. They can survive in water that isn't up to par, but to really live a long healthy life they need it very clean. All tanks need at least a weekly partial water change anyway. If you already do that, great. If not, try it and you'll soon see an improvement in all your fishes' health and vitality. If you could get back to me with more information such as; Tank size, filtration type, water change schedule, type of food, what other fish you have, etc., I may be able to help more.

At Your Service;
Chris Robbins