Angelfish can't seem to stay upright?

you never should have done a 100% waterchange

Check your nitrite levels, your tank may start going through another cycle because of the complete change

You're only suppose to do partial waterchanges of 25% with a gravel siphon weekly

did you at least condition your water before you put him in there?

did you check the temperature?

Did you acclimate him before putting him back in there?

EB

I have 2 big angelfish and 1 angelfish. the little one is tilted a little and was haveing a little difficulty swimming i did a 100= water change and put the conditoner in the water before he started going tilty. ls he just not used to the water or something?

You should never do 100% water changes, it causes extreme stress on fish. The problem may have been that the water was either too hot or too cold. The most water that should ever be changed at once is 50%, and I never go any more than 40%.

Nosoop4u

You should never do a 100% water change--it gets rid of the beneficial bacteria in the water. With that said, no one will be able to tell you what is wrong with your fish without more info. What size tank? What are the water parameters? (ammonia, nitrite, nitrate) How long has the tank been set up?

It could be bloating try starve him for a 3-4 days to let it clear out.

This is caused by eating floating flakes while taking air from the surface.

Try sinking the food and feeding them less to prevent it from happening again.

Hope this helps

WT

did you put enough conditioner in the water and make sure the water is the right temp