Betta's poo is white and stringy?

[freeflow246]

I was gone for about three days and left my bettas home. I had my grandmother come by and check on them the second day, and she said that they were fine. I came home really late last night, and Sushi was doing just fine, but Jalen not so much.

The brown algae in his water had boomed, so much that the water was cloudy with it. He was hovering near the surface, kinda bleh, and there was a long string of white poo hanging from his belly. I've heard that white poo can be cause by constipation, stress, and bacterial infections. He wasn't constipated; he hadn't been fed since Monday. He could have an infection, since I added a new moss ball the day before I left (but Sushi has the other half of that ball, and he's not sick), and he could be stressed, since the book that I usually keep between their tanks had been moved.

I immediately did a 50% water change and removed the new moss ball, and today he looked a little better. I put the book back between them too.
Any idea what the problem is?

Housing
What size is your tank? 2.5
What temperature is your tank? 78
Does your tank have a filter? no
Does your tank have an air stone or other type of aeration? no
Is your tank heated? yes
What tank mates does your betta fish live with? none

Food
What type of food do you feed your betta fish? bloodworms and pellets
How often do you feed your betta fish? twice a day, with fasting once a week

Maintenance
How often do you perform a water change? twice a week
What percentage of the water do you change when you perform a water change? 1 50% change and 1 100% change
What type of additives do you add to the water when you perform a water change? stress coat

Water Parameters:
Have you tested your water? If so, what are the following parameters? n/a

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? a little pale
How has your betta fish's behavior changed? not as active
When did you start noticing the symptoms? when I got home
Have you started treating your fish? If so, how? a 50% water change
Does your fish have any history of being ill? nope
How old is your fish (approximately)? no idea

[Oldfishlady]

I would just watch him for now and make another water change tomorrow and feed small frequent meals of good quality varied diet and see if the white poop will resolve on its own...it may be due to limited food intake or eating microorganisms in the tank...if it doesn't resolve within a day or so...it may be internal worms.....

For females, white poop can be normal on occasion due to either eating their unripe eggs or reabsorbing them-which they do on a regular basis....

[freeflow246]

Thanks! I'll keep an eye on him for now. Since this morning he's seemed normal, no more white poop, active, etc. But I'll post here if something doesn't seem right.