Looks to me ya need to make a decision on what way you want togo with your tank. Your current stock of fish; 2 Oscars, flowerhorn, 2 red bellie Ps and some convicts, means you will need to forget about having live plants. Also I assume all these fish are small right now, but in a few months you will have to start rehoming some of the fish. I would look into building a low cost Do it yourself wet/dry.
If you decide on keeping the plants and getting different Plant friendly fish, Don't buy any extra filters the fluval will be enough. For plants to do well you need 3 things, Light, Co2 and fertilizers. If you do decide to go with the planted tank, set up a post in the planted tank forum for advice.
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