PDA

View Full Version : 2 filtration questions



simmo2302
Tue Sep 01, 2009, 12:55 AM
1. when it comes to cannister filters (or just filters in general) is there a recommended amount of filtration needed ?

ie. 4 times the volume of water per hour (250 litre tank = 1000L/hr filter)


2. there are a wide range of filter media options, are there any do's and dont with these options?

(ie. sponges,foam, carbon, bio rings, & other compounds that remove specific things like ammonia, nitrates, etc etc.)

(i am just running a basic, filter pad & ceramic bio ring setup at the moment)

xrboy_85
Fri Sep 04, 2009, 02:09 AM
Hi Simmo

I am no expert but ill throw my 2c in to try and help

my understanding is about that 3x ltrs = ltr/phr

your sponges are for partical removal, bio balls/ noodle are for good bacteria developement this will help with keeping water conditions stable.

carbon media is for removing things like medications and should only be there after your fish are better.

ammonia/ nittrite remover etc i dont bother with due to doing regular water changes. water changes are your friend and the easier you can make doing this the happier you and your fish will be.

and i quote a user on the forum hear who states " dilution is the solution to polution" which has always stuck in my head!!

and always clean your filter with tank water not tap to avoid killilng your good bacteria.

Hopefuly this is helpful if anyone notices something here is not right please correct,

Regards Justin

ILLUSN
Fri Sep 04, 2009, 08:48 AM
with canister 2 things you NEED to remember real world flow if diffrent to flow rate on the box (usually tested empty with 0 head height.

its media and contact time that do the filtration NOT flow rate!

aim for a flow arte of 2-3x the volume of the tank and AS MUCH MEDIA CAPACITY AS YOU CAN GET!

with media your maily after biofiltration so high surface area medias (eheim substrate, matrix, bio max, hydroton/aquaclay, aquaone advance) are your best bet, as stated above carbon is short term only 1-2 weeks max and ammonia removers/scavengers are a waste of time.

mcloughlin2
Fri Sep 04, 2009, 09:09 AM
Probably one of the most important things to remember when selecting a cannister filter is that they very rarely pump out the water they say they do. The cheaper brands such as aqua nova, resun, orca etc are all rated with no media in them. In saying this Eheim are usually quite accurate with the estimated flow.

I think something that people starting out or who havn't quite researched filtration properly misunderstand is this; in a filtration unit you DO NOT want there to be excessive water flow. eg A cannister with a volume of ~8L that has a flow of 4000LPH will not have effective biological filtration. Therefore my suggestion to you is purchase a large cannister. It does not require an excessive flow rate because it is the amount of media it holds that is important. The most common media for a cannister is a fine sponge, a course sponge and then some media with a high surface area such as ceramic noodles, matrix or volcanic rock.

Once this media is in the cannister and in water aerobic bacteria will colonise it. They then convert waste (Ammonia) produced by fish and foods into nitrite and then nitrate. Therefore a setup with an effective filter will have no ammonia, no nitrite and some nitrate as it is difficult to create a habitat for anaerobic bacteria that convert the nitrate in nitrogen gas. The easiest way to reduce nitrate levels is via regular water changes. If you follow this then you will see ammonia removal sponges and other similar products are just another method for businesses to make money and are not required. If you find your setup has readings of ammonia or nitrite then you need more biological media.

simmo2302
Sat Sep 05, 2009, 06:26 AM
thanks 4 the info guys.

considering that the 1500L/hr aqua nova filter died when i got the tank (rescused the discus & whole tank setup) i am using TEMPORARILY a internal 700L/hr power filter which is running filter wool, sponge, and 1x ceramic noodle from the original filter.

i am looking into getting a fluval or aqua one cannister filter. i currently use a fluval 305 filter in my AFrican Cichlid tank, and am more than happy with the results.

the fluval in my cichlid tank, has a very large foam padding, and 6 media baskets. i am thinking of getting another one.

i have a 3 foot x 15 inch x 18 inch tank.

(91x38x45 = 155L overall volume but working capacity is about 140 - 145L i think )

so 150 x 3 = 450L, or 4 x 150 = 600.

considering that the filter would be sitting on the floor next to the tank & stand it would need to have a flow rate of 600 L/hr at 1100mm head.

(from the fluval manual i have, it works this out as being the distance from the waterline down to the bottom of the cannister filter)