Suction strength on Fluvall FX4 or FX6

[oldenred]

When it comes to cleaning the tank are these fairly powerful to use as a vacuum? I want to make sure that it will suck detritus off the rock work easily. I don’t have any need for this other than to vacuum my tank.

 

[Big G]

Almost bought one of these just to use as a vacuum. But the $$ gave me pause. The flow rate looks pretty good. And I like how you can recirculate the water back to the tank.

 

[dieselkeeper]

I'm thinking about getting one of these to filter the water after sand vacuuming and blowing off the rocks with a power head.

 

[rsumner]

Both the FX4 and FX6 have a vac attachment that you can buy as an optional ad-on and they do work pretty good. I had both models for two different fresh water tanks that I was running late last year. I considered keeping one of them when I shutdown those tanks, but decided to sell them to get a little bit of the investment back. I will tell you a few things:

1. you can get fine or super fine bags to work with the vac attachment, but they are both pretty expensive
2. both bag attachments will get clocked with sand if you intend on using it as sand vac also
3. you could skip the whole vac attachment but you'll be pulling sand directly into the impeller of the pump and will damage it
4. the FX series (especially the FX6) are really bulky and, unless you intend on leaving them near your tank, I'd find it a pain in the butt to move around just for maintenance
5. these units are pretty sensitive when getting them to prime. I suspect you'll find yourself spending at least 5 minutes after dropping them in your tank to get them flowing a full speed

With all the caveats I've mentioned, I've yet to find a great solution/alternative and anything I design on paper puts me back into a canister filter style configuration. <shrug>