What size sump for 200 gallon?

[Nature Scaped]

I have a 200 gallon with larger cichlids and catfish.
I’m looking at changing to a sump, I was offered roughly a 25 gallon one for free but not sure it will be large enough?

 

[altums85]

Bigger the better. For a 200 with your stock. I would atleast go with a 40 breeder at the minimum imo

 

[Caperguy99]

I usually use the ~20% rule - so 40 gallons, in your case.

 

[Danh]

In general at least 20% but it also depends on how its designed and used. I'd get the biggest box you can put in your stand.

The sump on my 120g is 30g used nearly full and I feel like I need more.

 

[Backfromthedead]

As large as you can go. I would look for something like a 75g tank.

 

[duanes]

I use a 125 gal tank, as a planted sump for my 180 gal tank.

but......
there are no hard and fast rules, its all about what you want out of your sump
is it most to add more bio-filtration?
Do you want lots of mechanical media for crystal clear water?
Do you want it to buffer pH and alkalinity by using calcium buffers?
For me , about 10% of the sump is used for bio and mechanical media and the other 80% is heavily planted to use up nitrate.

.....I have used 50 and 75 gal tanks as sumps for multiple tanks equaling 300 to 500 gals.

and
a 1500 gal pond as a sump for a 50 gal tank

 

[celebrist]

I use my 150 as a sump for the 450, more water volume is always good

 

[Midwater]

I would go with 25% to 50%, and filled with pumice.

 

[Danh]

pumice sucks...

 

[Backfromthedead]

pumice sucks...

Lol why?