Brief Answer:
Yes it can be

Detailed Answer:
Hi
Thanks for your query.

Dark colour stools may happen from bleed in upper Gastro-intestinal tract.

Krill oil has become available in market as source of omega 3, 6, 9. Unfortunately, omega 3, 6, 9 from these sources is not similar to the ones found naturally in human body. This causes them to have side effects. Most common is gastrointestinal side effects like diarhea, altered gastrointestinal flora, and sometimes can also causes gastrointestinal bleeding.

I will suggest that you discontinue krill oil. Also drink cleaner water from reverse osmosis filter to avoid any gastrointestinal infection during the process.

If there is any bleeding, it will stop by itself in 2 days. If it persists please see your doctor.

Hope it helps. Let me know if you have any other queries.
Dr Vaishalee

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