Bad impact with overspec skimmer
 

I am using PM Bullet3 for my 75Gal tank + 20Gal sump. I know this skimmber is overspec to my system. Do you think an overspec skimmer makes bad causes to my tank?
BTW, I change my water 3gal/wk at least.
My sps color are kind of faded away. But it can be said pastel color.

Nitrate, Nitrite and Phosphate are not detectable.

if you make a big change like this, then the next day you can see ill results. I have no personal experience with that skimmer, but can you turn it down? If not, can you just run it part time so your tank can adapt? Or... you could always feed more (which is what i like about a big skimmer...allows you to feed more).

what you are probably seeing is the zooxanthellae affected by the rapid depletion of their nutrients (po4 and no3 via organics)

Feed more.

Kip and chris4869,

Thank you for your supports.
I am planning to stop the skimmer for 8 hours a day.
When I feed more, is not it increased PO4? I want to maintain Po4 as less as possible.

Don't worry. Your oversize skimmer will keep it in check. I'm running a low nutrient tank, and I have to feed more to keep the color from fading.

I'd feed a lot more ... not giant feedings, but I'd feed more smaller feedings every day scattered through the day.

That's a generally energy inefficient skimmer [needs a power-hungry pump to run well] ... and it likely would be a lot cheaper to run a less overkill skimmer/skimmer-pump.