As millworkman says. Pretty much nothing to be done about gaps...touch up pens are rather easy to find for the areas that look a little rough.

So there is no way to put something in them to stop them from filling up with white plastic pebbles from my self cleaning cat box? It looks really bad... I was contemplating putting clear caulk in there...

That's disappointing to hear that Bellawood is low quality. It was one of the most expensive ones in the store I got it at. For future reference, what are some higher quality brands? Can they not be found at a place like Lumber Liquidators? Should I have stayed away from prefinished floors? Kind of wish I could just refinish them to fix the places that are damaged.

I wish the contractor had recommended replacing the subfloor, but he probably should have used a leveler on top of the existing subfloor even if he wasn't planning on replacing it. One of the things I am most unsatisfied with about the job. Frustrating to gut your entire apartment and then still have unlevel floors...

Putty is your buddy.

He says normal? That would fit with 'production workers'. IE: Guys used to get the job done fast.

Find a good matching caulk if it's severe. In my earlier installation days that's what we had to use on Bruce hardwoods.

"Can they not be found at a place like Lumber Liquidators?"

LL and other similar chains sell an affordable product to the masses. It's all about hitting the sweet spot (price) for profit. Next time you'd be better off, budget allowing, by going to a specialty store that deals in hardwood floors day in and day out.

If the subfloor wasn't prepped properly, there's your culprit.
If any of the planks have been gouged, the proper way to fix this is to cut out the board and install a new one.

How do you cut out a board if they fit together tongue and groove?

Putty or caulk? Do you have any links for products I should be looking at?

Essentially you cut out the board basically removing the tongue and or groove. And put the replacement back in with adhesive. Pictures would help with the putty / caulk question as it depends on the finish.

A professional will cut the centre of the board along the long axis. And then create a little triangular cut at the short ends of the plank. S/he will then pop out that plank and then TRIM OFF the TONGUES of the planks surrounding the hole just created.

S/he will then use wood flooring adhesive on around the perimeter of the hole and then drop in a new plank. Wipe up the excess glue with a clean, damp cloth. The plank will then be allowed to cure for 24 hours (avoid walking on the plank).

In my neck of the woods, an independent wood flooring installer will charge $50 - $80 per plank to make such repairs. If there are more than a 3-5 planks, the installer will offer a "job" quote rather than a per plank quote. Rates are HIGHLY dependent on location and local labour markets.

Puddy is more common with wood. Caulk is not normally used with wood.

We've had Bellawood in our house for 14 years and it has held up beautifully. Just saying...