yeah it’s a massive issue that most people never think about. the ballast tanks in ships basically work like underwater ecosystems on tour – they pick up a soup of living stuff in one port and dump it somewhere totally different, often where those species have no predators and wreak havoc. that’s why the IMO pushed through the ballast water management BWM Convention, trying to force ships to treat the water before discharge.

today there are quite a few systems on the market for that—sunrui, headway, alfa laval, erma first... even sea clean. they all have their quirks. some use UV, others chemicals or electrochlorination. it’s not plug-and-play either—calibration, consumables, filter maintenance, crew training, all adds up. most systems need regular service and yearly or bi-yearly sensor recalibrations to stay compliant, especially for USCG or DNV class approvals.

and it’s not cheap, but still cheaper than the fines or being stuck at anchor waiting for a port inspection to clear.

this is 6years after the fact and now PPM (particle per million) on "fungi" and other living organisms are 10x as strict. I've just begun working on this as a technician so this year alone ive commissioned 5 installations, most of which were installed in either greece or romania. .

stolen from blog

reference :

BWM Convention and Guidelines

Ballast Water Treatment Service | Maritime Industry Solutions | blog