Filtration Help

[Tom500]

I have a 8ftx30"x30" tank, i am unsure of the volume but i have 3 Fluval FX5's and an XP4 filtering it. I am doing two 25% water changes per week and still the tank isnt crystal clear. The stocking is quite heavy but no more than most 8ft tanks i have seen, infact less than a lot of peoples 6-7ft tanks, so i am confused as to why my tank isnt crystal clear like my other tanks.
Could anyone advise?
I am thinking of getting a huge pond filter to help things, can anyone advise me on what filter would be best given that iont have much space next to the tank, i was thinking a "Fish Mate Bio UV Filter 45000"??

 

[T]

fx5 should be really good at mechanical with all the polishing pads inside. is there floating particles or just cloudy water?

 

[Greg Curtis]

Try some Purigen in the filters. I use it in both my FX5's and my tank is crystal clear. Good stuff!

 

[tcarswell]

Ditto the purigen. Also do you run carbon at all? And what do the impurities look like? I doubt its floating matter... Maybe micro bubbles? A slight white tint to the water? I need a little more info on whats hindering your clarity and what it looks like. How old is the tank what is the stock etc...

 

[tcarswell]

Your tanks gallons are 375 BTW

 

[tcarswell]

fx5 should be really good at mechanical with all the polishing pads inside. is there floating particles or just cloudy water?

Noo , No polishing pads in FX5's

 

[Tom500]

Thanks a lot everyone for all your help, i really appreciate it.
It may have something to do with micro bubbles but mainly its quite cloudy for a long time after feeding, its like the filters are insufficient for the job but how can they be!
I have eheim media in one and the standard stuff it came with in the others i think i may need to change the media.
Thanks again

 

[Tom500]

Your tanks gallons are 375 BTW

Cool, thats fairly big lol

 

[tcarswell]

Not a problem man. And yeah thats a big ass tank