Canister Filter Dilemma

Hi all Gurus,

I have a Juwel Aquarium, 3.2ft(L) x 1.3ft(W) x 1.6ft(H), which houses a 6 inches silver arowana, running on a Jebo 828, 4 ply canister as well as a Five Plan 2ft(L) x 1ft(W) x 1ft(H), which houses 3 parrot fishes & 1 oscar, running on a Jebo 835, 3 ply canister.

I will be moving to a bigger tank soon, 5ft(L) x 2ft(W) x 2ft(H) and putting all the fishes together. The tank is a low profile tank without a sump.

Should I use both canisters for the tank? Or will the Jebo 828 be enough? Or should I just get a new canister for the 5ft? (I am actually looking up on Eheim & Fluval currently, but just looking around though…)

I am not considering an OHF as I have been using canisters all this while. And due to the 5ft tank's low profile nature, it fits nicely under my tv in my room so an OHF will only be an obstruction. I am still open to your expert opinions, nevertheless.

Looking forward to hear the response & advice from all the Gurus. Thank you in advance.