Why Is My Tropical Fish Tank Green

How to raise a PH in freshwater tank?

Hello!
I have a 55 gl tank with 3 tiger, 3 green tiger, 3 cherry, 2black ruby barbs, 3 kissing gourami and 1 pleco. Two weeks ago I decided to get few sharks. To my knowledge parameters of my tank water were good, but I am not an export and i took a sample of the water to the pet store. The clerk said my parameters were excellent. I’ve purchased 3 red-fin sharks. Three days later they died. I went back to the store and explain the situation (I wouldn’t get a new fish if I knew I had some problems with the water). Anyway, at this point another clerk pointed out that my PH is low and sharks together with most of the tropical fish prefer 7.0 PH. My PH is always at 6.0 or lower. I guess my other fish got used to 6.0 PH. THe clerk told me to use “Neutral Regulator” by Seachem. I’ve been adding it to the tank every other day for over a week now, but my PH is still at 6.0 or less.
Can someone tell me why I can’t adjust PH? I really want to add few sharks to my tank.

Thanks a lot.

See your on the wrong track here
what happened is you over loaded your bio filter. All the extra fish wast is what killed the fish not the ph.
The overload of wast is what made your ph change. You dont want to change your ph unless you trying to kill the other fish.

Do a 50% water change let your levels get back to normal and for get the ph it was fine and it will be fine again if you leave it alone.

Oh and for get the red-fin sharks they get way to big for a 55gal.

My tropical fish tank before the eclipse/sun catfish ate everything.