Aerate multiple times?

I brewed a Belgian Dark Strong Ale yesterday with an OG of 1.084. I aerated for about 90-seconds with an aeration wand and pure oxygen. It had krausen and good activity approx. 6-hours after pitching yeast.

The yeast is Wyeast 3522 Belgian Ardennes that was stepped up to make a 2.5L starter.

Nothing is wrong at this point but I was wondering if there would be any benefit to hitting it again today with another shot of O2 to help ensure full attenuation.

Thoughts?

You could but I probably would not. Since you made a healthy starer and hit it with the O2 I think you will be just fine without doing it.

'Yeast' advocates a second dose of oxygen at 12-18 hours with beers over 1.080.

I have given a second dose (based on that recommendation) and I have also not given a second dose with beers over 1.080 and have achieved expected attenuation and no off-flavors with both methods.

If this is the first time you brewed this particular recipe, then it's hard to say but it certainly won't do much harm to give a second dose if you keep everything sterile.

If you brewed the recipe before and had yeast issues, then yes, I would give a second dose.

This is my first time brewing this recipe so I'm not sure how the attenuation will turn out with this particular yeast.

Mash temp. was 152-153.

It's now in the temp. controlled ferm-chamber at 65-67* F.

I have used that yeast but not in something that high (mine is a Belgian Pale Ale). It attenuated very nicely, about 6+ ABV.

Most of the O2 is required when the yeast are building their cell walls and getting ready for the exponential phase, So I would say by the time you are seeing krausen there is no longer a benefit from additional oxygen.

I brew RIS of 1.1 OG few weeks ago and i did 2nd aeration after 14 hours, it went to 1.020 SG in 7 days

For 1.084 I wouldn't bother, but at 1.1 I definitely would bother.