# New external filter for Roma 125



## swackett (30 Mar 2015)

Hi,

I have a 125 litre tank which has is planted with Java fern, anubias, and crypts and has a selection of corydorus, lemon tetras and rosy tetras.  The tanks also is injected with a low level of co2.

We currently have 700l/h Eheim running which I think is not powerful enough to distribute the co2 and effectively clean the debris that collects.

Is the 10x rule (10 x volume = flow) still the rule of thumb?  If so I guess I should be looking for a flow rate of 1250 l/h.

With this in mind I was looking at either the Eheim Pro 3 600 + hydor inline heater or the Eheim Pro 3 350T, both of which come to about £260.  The other option I am looking at is the Eheim Pro 3e 600T (with the flow turned down)

Any thoughts most welcome on the above filters

Thanks


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## Wisey (30 Mar 2015)

I bought the Eheim Pro 3e 600T for a TMC Signature which is about the same size. Although the pump rating in their stats is 1850lph which more than gives you the 10x, the actual filter rate is factory limited to 700lph. I think this is taken in to account in the 10x theory though, it's 10 times the manufacturers rated amount as you know in reality you are getting half that. I don't have my aquarium set-up yet, so I'm afraid I can't comment on the filter performance and whether it needs to be run on full power or turned down.


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## swackett (30 Mar 2015)

Wisey said:


> I bought the Eheim Pro 3e 600T for a TMC Signature which is about the same size. Although the pump rating in their stats is 1850lph which more than gives you the 10x, the actual filter rate is factory limited to 700lph. I think this is taken in to account in the 10x theory though, it's 10 times the manufacturers rated amount as you know in reality you are getting half that. I don't have my aquarium set-up yet, so I'm afraid I can't comment on the filter performance and whether it needs to be run on full power or turned down.



Oh, did not realise that it limited to 700lph, how did you find this out? 

I have had the 600 and a pro 3e 700 in the past, very good filters.  I am leaning towards the 600T, however it is very expensive.  Will you setting up the tank in near future as I'd be interested in hearing what you think of 600t?


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## Wisey (30 Mar 2015)

I found out from the instruction manual, I'm not at home, but I just downloaded the manual from Eheim and it's not the one I have at home, it does not include the different rates. I had 3 different manuals come with the filter and it may have been in the one that talks about the electronic functions rather than the filter manual and I can't find that one online at the moment. If I can't track it down, I'll post again this evening once home. 

I'm afraid it is going to be a while before I get my tank set-up as I have some boring real life things to pay for before I can invest in my CO2 system and the plants to get things setup.


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## Wisey (30 Mar 2015)

Sorry, my bad, its rated at 1850lph pump rate, the filter is factory set to 700lph, if you increase it to the max, it is 1100lph. You don't get the pump rated 1850 though.


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## swackett (30 Mar 2015)

I just had interesting conversation with one of the importers of Eheim, the pump output for the 350T is actually 1250 lph not 1050 lph as stated.  The same pump head is used for the 350, 350T and 600.  The only difference between the 350T and 600 is the canister in 350T has the heating element and therefor has one less basket than the 600.

So I may opt to go for 350T as it is half the price of 600T.... decisions, decisions


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## Wisey (30 Mar 2015)

The 350T and the 600 probably have the same pump, but the 350T and 600T are different pumps. The head rating on the 600T is considerably higher which I guess is beneficial depending on the height up to your aquarium and if you have inline CO2 etc. I'm sure the 350T is adequate, I just wanted to avoid having to add powerheads inside the aquarium so went for a higher power from the start in the hope that more flow is always going to be beneficial.

This difference between the pump rating and the actual filter rating is there throughout the range from what I can see, but they don't seem to list it in the manuals of anything other than the ones with variable flow controls. The 2076 is pump rated at 1700, but has a max of 1000, factory set at 650 and minimum 350, where as the 2078 is rated at 1850, max of 1100, factory set at 700, minimum of 400. The pump rating is higher than the filter as a whole is able to deliver.

As far as I can see, you always get considerably less than the magic number in the advertised spec and like most technology, it is the law of diminishing returns, you have to spend a lot more money to get a little bit more performance. My suggestion would be buy the best you can afford and think is sensible, I know the 600T is crazy money, the 350T is a much better price, you can always add a powerhead at a later date if you feel you need more flow.


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## swackett (30 Mar 2015)

Yes the 350T and 600T are completely different as the 600T is a pro 3e.  The guy I spoke to said the rating on the box is the rating of the pump head, without any media, or pipes, and any height.  The pump head is just put into water and flow rate measured.   He said that the actual flow rate could be half of the stated rate, so a stated rate 1250 lph could actually be about 625 lph once you add media, piping (the longer this is the less is pumped) and ask it to pump against gravity.

Given this the actual rating of my Eheim 2124 is probably abut 350 lph rather than the 700 lph stated on the box

You are right also about the "buy the best"

to get a 600T or not, that is the question


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## Wisey (30 Mar 2015)

Have a think how big your cabinet is, the 600T is a fair bit taller and the struggle I am having now is fitting the plumbing in my TMC Signature cabinet as I have Eheim double taps for various things. I'm about to attack the cabinet with a jigsaw at the weekend...


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## swackett (30 Mar 2015)

Have been thinking about that.  Our Roma 125 cabinet (old style) has doors that are too narrow to get even a 350T in, so I am going to have to replace that with a new style Roma cabinet which will be able to fit in both filters as it has no internal walls and larger width doors.


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## alto (30 Mar 2015)

If you add in external "dams" such as the hydor or inline CO2 reactors, even those eheim taps, each addition will cost you "flow"
I'd go with a heated filter if possible


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## swackett (30 Mar 2015)

Decided to go for the 350t in the end.  I had a 2078 (same size as 600t) a few years ago and it was big and when full of water, heavy to move. The 350t will give me 10x turnover so I'm happy.


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