Will be setting up a new home for my baby Oscar in the new year. Looking at upgrading to a 6'x2'x3' tank @ approx 270G. Trying to decide on the best filtration to use. Bertie is only 3.5" at the moment and will be sharing his home with 4 Pims and a Plec, so fairly big filter requirements. Would I be best going for a sump, a sump and an external or 2 externals? If I go for externals would a fluval 405 and an Fx5 do the job? I always try to understock my tanks and overfilter them.

I am not qualified to answer your question.......... just wanted to say welcome to the site!

I'm a big fan of a sump.
Very practical, i only have to replace my prefilter cotton every week.
The rest of the pre filter is only cleaned when flowrate decreases.
I never cleaned the media within the sump since i got it.
I use a 5 foot sump on my 6 foot tank.
And it copes with my bioload. My tank is kinda packed.
I use canister and HOB filters for my smaller tanks, but prefer a sump on my big tank.

If I was in your position I would opt for two beefy external filters. I personally would go for a couple of Eheim professional 3', each one able to handle 1200 L, but they are very expensive. A slightly cheaper option would be a couple of FX5's. There is absolutely nothing wrong with a sump filter, I have got one on my 300 gallon and it does a grand job. However, installing them isn't exactly straightforward and unless you are using a very large freshwater aquarium, I really don't see the benefit in using one.

I guess i've become a bit biased as i had lots of trouble getting my canisters flowing again after cleaning...
Air trapped in hoses and in the motor.
Never had that trouble with the sump.
And the sump came with the tank,so no trouble installing it.
i never heard of a sump, until i got this tank.

I think a sump filter comes into its own on a big tank that is very heavily stocked. I have just been looking at the specifications for the FX5 and it stays if his self priming, meaning you just switch it on and it will start working which is a great benefit to many people, there's nothing more frustrating than cleaning your filter and then spending ages trying to get it to work again.

Thanks guys, you've helped to clear things up for me. Wanted to be sure that the canisters would do the job, so will be going with them. Already got one Fx5 so just need to get another one.

yep self primes. and is a very good filter. £££ wise i don't think you can get better. make sure you fill it full of water before turning it on though or the ceramic coating will wear on the impeller. it will only self prime if it has at least a little over half fill of water.

for a 270g i would go with canisters. with models like fx5 and ethiem pro3's sumps are loosing the battle. the way i see it, if you have 2 canister you get 2 pumps so more water flowing through. if you build a sump with a single powerhead you get a lot of bio media but not a lot of circulation. you could add another powerhead but then you may as well have 2 canisters. with canisters able to cope with 400g tanks why have the hassle that sumps can give.

sunnybunny wrote:


Get a sump to go with your FX5 - is what I am running

Apart from offering to sdupport a bioload that no canister (no matter how big) can match (due to the capacity for media), you can do soo much more with a sump. ie:

- refugiums
- hide heaters / thermometers
- add/ remove media easily (without having to turn things off)
- aerate your water

Sumps also add water volume to you tank which helps stability.

In theory I agree that a sump filter is one of the most efficient filtration systems you could have. However you have to remember that filling a large sump filter with media is quite expensive. My sump filter is probably around 40 gallons and I have got 20 kg of alphagrog and over 1000 bac-balls in it, and there is still quite a lot of room. I think I have enough media to service well over 1000 gallons, my tank is 300 gallons.

I think it's all very well going for a massive sump, 100 gallons, wow!, but is it really worth it at the end of the day? Personally I think that it's a little overkill. How much more beneficial is it going to be having enough media for 5000 gallons when you've only got a 250 gallon tank? Yes you are adding that much extra water to your system, however you still have a limit on how big your tank is and how many fish you can actually fit in it.Very big sump filters are best left for ponds.


Personally, I would stick with canisters and see how you get on, I reckon you'll be just fine, no need to go to all the trouble of plumbing in a sump filter when at the end of the day, it really isn't going to benefit you that much more than having a couple of beefy canister filters.

get 2 fx5 theyr pretty big pwerful filters and there cheep,
sumpl are hard too set up.