Well, whether the filter is sufficient for your tank's bio-load will depend on many factors... like the size of the gold fishes, how much and how often you feed them, how frequent and how large your regular water changes are, how often you clean the tank and filter and the quality of bio-media you use etc.
The more time and effort you spend maintaining the tank, the less work the filter needs to do. Conversely, the better the filter the less time and effort you need to maintain the tank. So its all about time/effort vs cost.
Theoretically, the Ecco Pro 300 will be sufficient for the setup, if you stick to regular tank maintenance. But if you find that ammonia and nitrates keep spiking up, and you are already doing plenty of cleaning, water changes and controlling feeding... then it'll be an indication that you need to upgrade the bio-media or upgrade to a better filter with more filtration capacity.
Ultimately it all depends on your budget too, if money is not an issue, just get the largest canister filter you can afford, more filtration is always better then less.

Bookmarks