Skimmer on a timer?

[Megatron]

I've been tossing the idea around for some time now. I'm considering running my skimmer half the time I do now.

Nitrates 0
Phosphates 0

I run biopellets. I know that you need the skimmer to run biopellets because increased bacterial biomass and growth will decrease the dissolved O2 levels in the water column. With that said, I believe I have enough gas exchange when my water hits the refugium.

The reason? I'm trying to figure out why the growth of my corals has slowed. Growth was at an all time high when I ran a Fluval FX5 and my nitrates were at constant 40ppm and my phosphates glowed blue in the test tube. Sure the colors weren't as deep as I'd like, but not that far off.

The growth slowed after these reasons:

1. Switched to Salinity Salt mix from Instant Ocean and I dosed everything. (without testing) Now I've switched to Kent Reef Salt.

2. Switched from a 6 bulb T5HO light to LED. (ReefBrite 48" fixtures) Now I'm running 2 LED ReefBrite fixtures and 2 x 150w metal halide.

3. Added chaeto algae that grows really good in my refugium.

4. Got a skimmer rated for 130 gallons on my 90. (Reef Octupus BH300)

5. Stopped using carbon in my tank.

I still use tap water. Never had any problems with it.

So, am I making a mistake doing this?

[AZDesertRat]

My thoughts are any piece of equipment that is not running will contain stagnant or low dissolved oxygen water that will slug or shock the system when turned back on.

What do you know about your tap water? That would be my first change, I made the change about 20 years ago myself and never regretted it. I used to be the manager of the water system so knew its quality but still chose RO then ultimately RO/DI so I alone have total control and faith in my water quality. Will I drink the tap water? Absolutely. Will I put it in my tanks, absolutely not.

[Megatron]

I have used rodi before. For about 6 months. I truly didn't see a difference. My tap water is not bad at all here in Detroit.

[MizTanks]

Use a TDS meter on your Detroit tap water lately? Give it a try :)