Fluval U4 V 305

[Doogz]

Finally bit the bullet and have ordered a Fluval 305 to replace my internal U4.

Problem is I've just found out both have a flow rate advertised at 1000lph, one of the main reasons I went for the 305 was because I assumed it would have a higher flow rate, one of the benefits being better surface aeration.

Can anyone with experience of both filter tell me if the 305 outperforms the U4 in real terms?

Also, will the U4 sponge pads fit in the same space as the 305 pads?

Cheers!

 

[Mowbz]

There is no real difference in flow, only in filtration. The 305 obviously has much more room for media, therefore can handle a bigger bioload.

You should be aiming for around 5-10 times the tanks volume in l/ph, so your 1000 l/ph is just about sufficient for the 200L in your signature, but considering its quite lightly stocked, thats not going to be an issue (Unless its packed out wals to wall with plants?)

The media from your U4 (I have a U2 in a 72ltr QT/Hospital tank, they're brilliant) wont "fit" straight into the media trays in the 305, but you can cut sponges up however you like to fit. I would recommend shoving all the media from your U4 into the external. This will mean you are instantly cycled for the current bioload you have. The bacteria will then in time start to inhabit the rest of the filter media in the 305.

Hope this helps.

Ben

 

[Doogz]

Thanks Ben.

Shame, I was hoping for a bit more suface agitation without having to have the airstone pumping all the time. Will just have to see what it's like when it's up and running.

I'm just going to cut up the sponge, chuck that in the bottom of the filter, biomax in the middle, polishing in the top.

Just got to massacre my tank lid now

 

[Mowbz]

Ive massacred a tank lid before to fit a new lighting kit. Shout if you need any help with that bit, Its pretty simple! I took my time with it because i didnt want it to look like it had been fiddled with, so my "butchering" was quite methodical really!

You'll certainly get the better surface agitation so you can remove the airstone. Most externals come with a spraybar to send the water back in, and if you set this up right, you can make a right mess of the surface and in some cases it can be so extreme you'll upset your fish, so i wouldnt worry about that, you can either make small waves, ripples, or aim them upwards and let the water bomb back down into the tank. There are lots of ways to get the water back in and moving

I have a 1400lph external that actually has quite an impressive return pressure considering how far the water goes, and it can push plants around 4 ft away at the other end of the tank, even when aimed underwater!