aquarium filter is best, under gravel filters or standard filters hanging?

I have several fish tanks and I am having constant problems with clairity water. do 10% weekly changes of water (I tried once a month by 25% as the pet store recommended, but it was not help.) and I can change the filter every two weeks. I've tried chemicals, but his singing kept clear. Meanwhile my friend has a 55 gallon that have never changed once the water which need to add water when low. but they're tank is very clear, I've never seen one so clear. The only difference is that using both a pendant and plate and filter. I have read many positive and negative things about UG filters and was wondering which is better and / or if I use both? The filter has a capacity of 55g tanks and mine is only a 44g i only feed twice a day, as well as those who eat in 3 minutes, just empty. filter media is full of blue sponge flakes carbon. that are more or less the standard for basic filters.

UG filters are not really considered a good idea nowadays. One problem is that the circulation through the gravel is too fast for a lot of plants so that their plants are doing poorly. They also tend to suck a lot of ground through the gravel and leave it directly on the glass bottom of the tank. Not being able to see the dirt, does not mean that will not degrade water quality. Do not change the filter every two weeks. Rinse foam filter or any material that is used in water filter on the same temperature as the water in the tank each time the filter output is greatly reduced. If you change the filter every two weeks, the good bacteria never gain a foothold:. Other possible reasons why the water is less than crystal filter is too small for the tank La. There are too many fish in the fish tank. are turbocharged.

55 Gallon Aquarium on Craigslist