# External for 70L planted tank



## glod (4 Dec 2007)

Hi folks, sorry for posting with a question straight off but I'm hoping for some opinions.  I am in the planning stages for my new 2ft (70L) tank.  It's going to be planted, not decided on high tech or not yet...
But I need a filter for it.  I was looking at the Eheim 2322 Professional filter with built in 150W heater but it has a reported 500lph flow rate.  Is that going to be too much ?  Should I consider a lower throughput filter with a hydor external heater ?


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## Tom (5 Dec 2007)

That Eheim should be fine. You can always turn the flow rate down if you find it's too much.


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## George Farmer (5 Dec 2007)

500lph is about right for 70L.  I'd actually consider more.


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## ceg4048 (5 Dec 2007)

Hi glod,
             You'll never get 500lph out of that filter unless you elevate the pump head to the same level of the waterline and if you don't put any media in the filter. That's how filter throughput is rated. By the time you situate the filter below the tank and add media you might get 250lph. If you add further restrictions like CO2, dirt etc. you''ll get even less. Ideally, for planted tanks you want between 3X-5X tank volume turnover per hour which for your tank, 70l X 3 = 210lph. That's why George mentioned he'd consider a higher  rated filter. As a general rule, always subtract about 50%-60% from any advertised filter rating to get the approximate true throughput. Eheim in particular are notorious for their optimistic throughput ratings.

Cheers,


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## Themuleous (5 Dec 2007)

Ive got a 2222 on my 90lt and if I had the money I'd probably invest in a second one as its not as much flow as I would like.  As George says, that one sounds about right.

Sam


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## beeky (5 Dec 2007)

The problem with 'good' flow though is that it tend to move sand substrate around. Over a few days I find my silver sand creating hills in the corners!


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## glod (5 Dec 2007)

Thanks guys!  
So if the throughput is borderline, does anyone have a recomendation that includes the capability to heat the water and has enough throuhput ?  The filter will be sitting approximately 4 feet below water level.
I haven't hunted too hard for prices but I reckon a budget of Â£130-Â£140 including media is feasible, of course If I can save some for more plants that's a bonus


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## ceg4048 (5 Dec 2007)

Well, thermofilters are few and far between. I love them but a lot of people are afraid of them. They are more expensive as well and most are not compatible with marine water so the market for them is stifled 

The next step up is the 2126 which is rated at 650lph but is a whopping Â£150 _without _ media.  Media set is another Â£23 so that will blow the budget to smithereens. If that's the case I'd just stick with the 2322. Really, I guess I wouldn't want to give the impression that the 2322 is necessarily "marginal".  I think it's just better to be aware though of  their silly throughput ratings. 

Since there is nothing in between this and the next higher rated thermo unit, simply be cognizant that your wiggle room is lower so don't go 3 months without cleaning the filter for example. Replace the pads a bit more frequently. Try not to let the tank get overgrown, which causes poor flow patterns. Try to limit the amount of restrictions you place on the return line and so forth.

Cheers,


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## glod (5 Dec 2007)

Wise words ceg4048.  I started out looking at the ecco filters with the thoughts of adding an inline heater.  As for CO2 if I do add it it will be pressurised this time and through a diffuser, I got fed up with changing the mixture on my old setup with the nutrafin ladder.
I don't think there would be any restrictions on the input/output other than possibly some glassware to keep it looking pretty.. that shouldn't restrict the flow tho.
I can pick up the 200w inline heater for about Â£35 and the non thermal canisters are a lot less expensive.  e.g. tetratec ex 700 claims 700L of flow and the two together would be a lot less than the eheim on its own.  So really I am  wondering if people think it would be preferable to go for the 2 part solution to the all in one as it were.


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## Ed Seeley (5 Dec 2007)

I've got a 2128 on a 40g tank and the flow is just a bit too high most of the time so I can just throttle it back slightly using the tap.  Personally I wouldn't buy a Thermofilter again.  I love having the heater out of the tank, but would buy a normal Ehiem with a Hydor on the outlet hose.  Whenever I clean the filter I have three cables to undo on the thermofilter which is a pain to a lazy guy like me!!!    The digital temperature readout is a nice feature though - shame they didn't sort out a rapid decoupler for the power too...


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## George Farmer (6 Dec 2007)

As a general rule of thumb I like to multiply the tank's volume by about 10 and go for that claimed flow rate. 

i.e. my Juwel Rio 125 has a 1200lph rated filter.

My 216 litre actually has 2750lph rating.

Substrate etc. getting blown about isn't an issue with lily pipes or spray bars.


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## ceg4048 (6 Dec 2007)

glod said:
			
		

> I can pick up the 200w inline heater for about Â£35 and the non thermal canisters are a lot less expensive.  e.g. tetratec ex 700 claims 700L of flow and the two together would be a lot less than the eheim on its own.  So really I am  wondering if people think it would be preferable to go for the 2 part solution to the all in one as it were.



Yep, this is also another excellent solution. I don't know much about the Tertratec but I haven't heard anyone bashing them. The Eheim pricing is a major deterrent and I agree with Ed that having all those cables to deal with during maintenance is a pain. Ed, you'll be glad to know they fixed that on the Pro III! One power lead, no telephone cable - whoo hoo!

Hey George, that's a great rule of thumb. Easy to remember :idea: 

Cheers,


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## beeky (6 Dec 2007)

Telephone cable?!!

Can you change the temperature of the tank from your mobile phone?!


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## ceg4048 (6 Dec 2007)

beeky said:
			
		

> Telephone cable?!!
> 
> Can you change the temperature of the tank from your mobile phone?!



Ha ha  Beeky that would be great if you could. That might almost make it worth the higher price... No, unfortunately not. The Pro II series use a telephone type cable to send temperature and command data between the heater unit at the base of the canister and a separate electronic thermostat/readout module. As Ed pointed out you wind up with three cables: one power lead for the pump, one for heater and this third data cable. Very annoying.

Cheers,


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## glod (9 Dec 2007)

Thanks guys.  I managed to get a good priceon a fluval 205 which is rated at 680lph.  Close enough to the 10x I was looking for


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