Lincoln Memorial Reflecting Pool Water Retested For Algae After Renovations

The Lincoln Memorial Reflecting Pool is literally under the microscope ... and TMZ DC spotted signs it's passing one scientific test ... at least as it relates to algae.

Check out the video ... workers spent time Monday roaming the perimeter of the landmark with glass jars attached to long poles ... scooping up water samples and bringing them back to shore for analysis. After each test, one of the workers recorded results on a data sheet.

We zoomed in on the paperwork and snapped photos of the results ... and, it seems the algae readings are mostly low.

It looks like algae levels were graded on a scale from 0-5, with zero meaning little algae. Most readings are 0s and 1s, but one result appears to be higher ... check the photos and judge for yourself.

Dissolved oxygen levels and pH measurements also were measured. We'll bet your local pool guy can tell you what those numbers mean, but we certainly do not.

The testing comes amid a chaotic stretch at the Pool. As TMZ previously reported, President Trump has blasted what he called vandalism at the site following multiple incidents, including arrests, involving visitors entering the water.

There are also concerns about the water's conditions -- including reports of algae and the discovery of a dead duck floating in the water.

While officials haven't publicly released their latest findings, the paperwork suggests the algae problem is trending in the right direction.

Of course, this is all following a massive makeover -- including the now-peeling blue paint job -- as part of what's ballooned into a roughly $16M project.