Fluidized Sand Bed Filters

[N1z]

Im reading my new huge marine book and a good form of filtering the water is a fluidized sand bed filter was in the book. So i went online to do some research on them and also see prices and i liked the look of them tbh but the price was £50 up but then i saw a link to ebay site which was whole lot cheaper! ive asked the seller about it and waiting for a reply but wot u guys think?
http/cgi.ebay.co.uk/Fluidized-Bed-Filter...0QQcmdZViewItem

 

[andywg]

They are ok, though can become a nitrate factory. Also, if the power is off for a small amoutn of time you may well find all your bacteria dead and have to start the cycle again.

They definately have their advantages, but I'm unconvinced of them in marine, or as a primary filtration.

 

[N1z]

well i wld be running live rock, external aswell but thats wot i thght its kinda like a under gravel. ok no worries as it saves my some money so idm really cheers

 

[Navarre]

I ran a fluidised bed last year for my sons 30 gallon system. Whilst it was great at coping with fast nutrient fluctuations it was also very poor on keeping nitrates down. It easily outcompeted the liverock and overpowered it so that nitrates were a real problem. I removed the bed and just like magic the nitrates dropped almost overnight!

 

[crazyelece]

IME and IMO they are great filters for large FOWLR systems with messy predator eaters. They should be backed up with nitrate reduction in water changes, live rock, DSB, and/or nitrate filter.