Need help on buying a new External Filter for my Aquarium.?

Well, 125 litres is 33 US gallons. I think that it would be best if you got a 30-60 gallon filter by AquaTech. I have this filter and it works great, it keeps the tank nice and clean, and since it takes two filters, double the clean. You can buy this product at Walmart seen here - a href="http://www.walmart.com/ip/Aqua-Tech-W-Bio-Fiber-Advanced-Biological-Filtration-Power-Filter-1-ct/10291977?povid=cat202074-env237414-module395372-rLink5" rel="nofollow"http://www.walmart.com/ip/Aqua-Tech-W-Bi…/a