1.grey color w red 2.dead fish 3.need hospital to clean tank 4 PH

Question

Hi Jeeva,
I noticed our bettas (separate tanks not by each other) had more color. As they settled in, their heads became grey and slowly continued toward the back. I read all the info & do not see a rust color to indicate Velvet. I do notice when I use a flashlight that there are red-like streaks around the gill area. Is this normal to have greyness &red streaks?
Also, we brought a small alge eater. It only lived  a few days, like maybe 5. We took it out immediatley, but only did a 50% water change. I know it's important not to get rid of all the good bacteria in the tank. Should we have done a full tank change? How do you not stress the fish when transferring to a hospital bowl?
And lastly I was told the PH was a little high on nitrites or nitrates. What does this mean?How do you fix it?Could that have killed the alge eater?
Thanks, Jenn

Answer
hi jenn.

you should never empty you tank. you should only do about 20-30 water change every week. When you changing the water make sure you treat it with water conditner. If your Ph and nitrates Etc.. is high, i would perfer you do 20-30 water change right away. you should also get cycle condiner, which will help your tank cycle and control nitare, ph, and other harm stuff.