In my research of filtration I have been trying to convince myself upon the correct filtration methods for my 400L colony tank and of course the two methods are, surprise surprise ... Canister or Sump.
Before I go further the tank setup is as follows: 400L volume with eheim pro 2028 and internal 600l p/h filter. the tank is currently stocked with 21 adult and a handful of juvenile bristlenose and with 25% wc twice a week is doing alright parameter wise...
(The first thought people might have would be recommending a second grow out tank but due to me wanting to have a chiller on my tank I wont be able to afford two tanks)
From my budget workings it appears that the cheapest method of filtration is to just add another canister (currently looking at a eheim 2217 rated for 600l aquariums)
This being said, as this tanks effectively has 7 breeding trio's I am expecting the amount of fry to be astounding and thus I will be in need of the best filtration around (or at least one that can easily handle such high bio loads)
So my first question would have to be. will 2 eheim canisters both rated for 600L aquariums each, with another 600lph internal provide a substantial filtration for 21 adults and perhaps 500 fry? seeing as both filters would provide around 6 liters of bio media capacity i'm expecting this to be enough area for BB to grow on but i'm not completely convinced. The main problem with this setup is likely to be the flow rate/turn over of only around 6 times per hour.
Moving on to the sump idea. The idea of a sump to me sounds like the best solution to my scenario as it will ideally be a 4ft sump adding another 200L volume which creates more stability in water chemistry while The area for holding bio media could be anywhere from 5L to 10L+ of matrix and it will also provide a great spot for plant growth to combat the nitrate buildup or provide a nice fry grow out area in the "fuge" "refugium", which addresses my two main concerns for such a breeding setup.
Now after writing all this, it sounds like i'm pretty much sold on the sump idea but the problem as always is cost. Considering all of the work involved in drilling an overflow and plumbing my current tank and then adjusting the stand to hold another 200 kilos of water it appears to be a smarter move would be to get a new tank, custom designed and made for this setup.
Which is where the money aspect comes into play. The canister filtration will cost no more then $300 where as the total cost of the sump will likely be around $750 including all the nice additions that the sump can hold.
If views/experiences can be shared it will very much appreciated.
Thanks for reading (if you were able to read the whole lot)