Not sure why members feel a fx5 is not enough for your needs? I have a 210 with fx5 and until recently housed a Cichla temensis, Cichlasoma ocellaris, Osteoglossum bicirrhosum, Phseudoplatystoma fasciatum, and Flowerhorn with no problems. Weekly 40% water changes were sufficient to control nitrates and nitrites and ammonia were 0ppm.
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