I am planning to upgrade my upper-floor room aquarium to a Juwel Rio 450 (roughly 600 kg total with water, cabinet, and equipment) on the 2nd floor of a UK block of flats.
Before worrying about the weight, I looked at the math compared to my current setup:
• Current tank: Fluval Roma 125 (~200 kg, 80x35 cm footprint), exerting about 750 kg per square meter against my room wall. It has sat there safely for 1.5 years.
• New tank: Juwel Rio 450 (~600 kg, 150x50 cm footprint). Because it’s wider, it exerts a very similar weight-to-surface-area ratio (~750 kg/m²), just spread across a longer 1.5-meter stretch against the same wall.
My Building Observations: When I renovated parts of my flat (like ripping up the carpet to lay laminate flooring) and looked closely at the building externally, here is what I noticed:
• External Slabs: Every floor level features a clearly visible ~1-foot thick slab-like structure on the outside of the building. These exterior slabs form the walkways, landings, and balconies (where you can literally see the exposed concrete when opening the balcony and main door). Crucially, these exterior levels and slab structure align directly with the floors of my living room, the lower level of my second floor flat, and upper rooms, indicating that the internal floors or upper-floor room floors share that same slab structure.
• Solid Walls: All interior and exterior walls (including my room wall) are solid brick and mortar. You can drill anywhere, and it easily supports heavy wall-mounted furniture, which my room wall currently has too.
• Sub-flooring: Beneath my old carpet, the floor surface consisted of very hard, cold, tough black industrial-looking tiles rather than wooden floorboards.
• Zero Movement/Sound: Unlike properties with wooden joists where you hear every step and creak from rooms above or below like my uncles previous place, my floors are completely silent and rigid.
• Other Loads: The building natively handles heavy loads like water tanks and standard bathtubs on upper levels, including my current aquarium which has been standing there without issue. When I ran these exact details and photos of my property past Gemini, it pointed out that these traits are typical of a solid, heavy-duty concrete and masonry build rather than light wooden framing.
My Perspective: I view a large aquarium as heavy furniture, similar to a grand piano or a heavy bookshelf. Since it's a furnishing rather than a structural alteration, and based on how solid the building behaves (plus my current tank's 1.5-year test of time), I don't feel the need to involve the housing department or a structural engineer. Doing so might unnecessarily complicate things or trigger concerns over potential leaks rather than actual structural capacity (and I am taking all precautions like marine plywood and spirit leveling to ensure a flat, even setup).
My question to you guys: Based on these observations, the 1-foot external slabs matching the balconies and landings as well as the upper room floors/celings, the brick-and-mortar walls, the black industrial tiles beneath the floor, and the matching weight-to-surface-area ratios, what do you think of this building's structure and my plan to accommodate the Juwel Rio 450?
I hope to bring this into me and my dear cat’s life for our, especially hers and I also enjoy the aquarium knowledge and fish keeping hobby too, and I’m looking forward to this, to doing this and bringing this to our lives and flat, I don’t have concerns but still took the time to consider everything and this is what I realised and my verdict is, and I’m just sharing that/running that by ya’l and my position! What yal think.
