Fluval vs Aquaone filters

[polerz]

I need another 200L worth of filters. I have a 640L tank and I am unable to use a cannister filter as I have no where to put it. I have already two internal fluval 4 power filters running with only 4 fish in there. Its a new tank so I think I have a little bit of time before I need some more filters?

Questions:
a) how much time do I have? The ammonia is at about .25-.5ppm (but its a new tank -around 3 days old- so thats acceptable atm.). PH is spot on.

b) The two fluval 4s will cover the filtration needs for around 400L of the 640L tank. So I need another 1-2 filters to do the rest of it. I was looking at these:
2 of these:
http://www.theaquariumshop.com.au/shopexd.asp?id=189

or the much more expensive fluval ones (around $89 each).
1 of these:
http://www.theaquariumshop.com.au/shopexd.asp?id=386

My question is, whats the difference between the aquaones and the fluval. I mean they are a simple design, sponge, bit of air pumping water through the spunge.

Am I right with the aquaones? Or should I spend the extra money and get another two fluvals ontop of the two I have.

c) Are there any differences between internal power filters like the ones above or external power filters like: http://www.theaquariumshop.com.au/shopexd.asp?id=372

Thanks alot guys

p.s. the tank is cold water, I have about 4 gold fish in there.

[Damon]

There is no way to tell how much "time" you have. Noone can predict the time it takes to cycle each aquarium. It varies on size and bioload and filtration.

The fluval has a clogging indicator. Not sure about the other. Never heard of it before.

Keep in mind that flow rates are based on running the filter empty (except eheims). Your flow rates will not be that high once filled with filter media and debris strarts to build up.

External (HOB) filters provide more biological filtration. Internal are more for mechanical filtration. Aerobic bacteria are much more efficient than anerobic ones but both are needed in an established aquarium.

[polerz]

well theres absolutely no way I can use a cannister filter with my tank, my only option is power filters unless someone else has a suggestion?

fluval vs aquaone?

[fnesr]

Probally a bit late for input on this but I use a lot of internals and have used a lot of brands available in Aust. The Aquaone's work well however in my experience they often get loud after about 6 months of use and the vibration noise of the impeller can drive you nuts. For the cheap end filters try using RESUN's, they are cheap, reliable and quiet. If your looking for more upmarket internals try the SONPAR (or TOTA - same brand) internals. I've got several SONPARS and they perform excellently and are dead quiet. This is a reveiw I wrote on the 1500/1800 models but they come in a wide range of lph and max head rates. ...

http://s14.invisionfree.com/RECICHLI...p?showtopic=12

The SONPAR/TOTA's are more toward the high end for expense but still cheaper then the fluval even at a 1800lph.

[IloveCichlids]

do you have room for HOB, I have 2 Emp. 400's on my 120 gal. and they work great, Dont take up much room either.