Big Sandy Lake vs Round Lake
Water quality, depth, fish species, and recreation comparison.
Round Lake has a higher water quality grade (B, Good) than Big Sandy Lake (C, Fair). Both are in Aitkin County, Minnesota.
Big Sandy Lake and Round Lake are both in Minnesota — a same-state head-to-head where the comparison comes down to lake-specific differences in depth, watershed, and monitoring history rather than the broader state-level water-quality regime. The grades are close: Big Sandy Lake (C) and Round Lake (B) are within one letter of each other on the LakeGrade rubric. The per-parameter sub-grades below will show where the small differences actually live.
With grades this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.
Big Sandy Lake
Murky, only visible to about 4.5 ft.
Round Lake
Good clarity, visible to about 14.5 ft.
Side-by-Side Metrics
| Metric | Big Sandy Lake | Round Lake |
|---|---|---|
| Overall Grade | C (Fair) | B (Good) |
| Water Clarity | 4.5 ft | 14.5 ft |
| Phosphorus | 29.5 µg/L | No data |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 84 ft | 27 ft |
| Surface Area | 6.1K acres | 553.5 acres |
| Public Access | Yes | Yes |
| Fish Species | 1 | 1 |
| Trophic State | eutrophic | oligotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Round Lake wins on overall water quality with a Grade B versus Big Sandy Lake's Grade C. Water clarity: 14.5 ft vs 4.5 ft. For fishing diversity, Round Lake also leads with 1 species.