Multiple tanks unit.


Feeder Fish
Original poster
Sep 29, 2019
Hi folks, thanks for taking a look.
I havejust been given the go-ahead by the wife and she has allotted me a nice space to fill with a tank or tanks, as long as it's not scruffy like my last build.😆

I currently have a 120 x 50 x 50cm 4ft 300ltr tank filled to capacity with various semi aggressive inhabitants aswel as a little 125ltr tank filled with peaceful fish.

I planned to upgrade the 4ft tank to a 5ft as it's got a fair few cichlids in. I have already got the 5ft tank sitting empty.

Now the plan has changed somewhat, I now have a convenient 9ft space and that means that I can have both tanks side by side.
This gave me the idea of a semi rack, keeping with the rule that it has to be smart, I can't just have a conventional rack, I am going to build a cabinet that has the 2 main tanks on top and they will both have there own smaller grow out tanks below.
I intend to run the 2 main tanks on a sump that'll be hidden in the middle and the 2 smaller tanks will run independently with internal equipment so they can be used to quarantine.
I have done some rough drawings, and I mean really rough, of a few different possible layouts. I will re-do them tonight neatly and ask your opinions.

I am posting here not only as a build diary but also so I can have the expert input of the community, I will no doubt be needing lots of help, so if you fancy lending a hand then stay tuned, it'll be much appreciated.

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MFK Moderators
Staff member
MFK Member
Jun 7, 2007
Isla Taboga Panama via Milwaukee

Although you only see 2 tank running to the sump above, there are actually more, the number of large bore pipes leading to it, indicate how many.
As long as you drill, or have HOB overflows, you can have any number of tanks on a single sump.
I usually ran 4 or 5 tanks, to each sump.

Sometimes with aggressive cichlid species, 2 (a comparable pair) to a tank may be the limit.
But some less aggressive ones shoals work well, it depends on the species
For me with aggresive cichlids, like Vieja or Parachromis, in 6 ft tanks a pair, or trio of adult fish per tank is what usually worked.
For less aggressive types like earth eaters the shoal technique worked well.