Build what you think look's nice and make preparation for handling dust. First and formost,use merv 8 or higher havc filters that FIT filter holder. Use a quality vaccum cleaner that doesn't just pick dirt up and redistrubut it. Use a long hose on the GOOD vac to quickly run over case and contents. If you one day change your mind you can always add doors.

How big is the aquarium? How will you access the filters? It looks like there is a door above the tank. Will there be adequate ventilation in that area to dissipate heat from the lights?

The aquarium will create a constant high humidity level, which will impact the surrounding wood. That will be a bigger issue than dusting.

We have several bookcases/entertainment center areas with open shelving, drawers, glass doors and solid doors. The open shelving needs dusting weekly(dogs and a smoker). The glass door shelves need dusting monthly to include dusting the art and knickknacks.

The easiest way to dust is a fluffy duster on a handle, then vacuum the dust off the duster. Have had several types of vacuum cleaners, from Kirby, Hoover, Shark, and others. The only one that minimizes dust is a Dyson.

I also have a Rigid shop vac with a HEPA filter(for my shop) which is actually better at dust control than the vacuums listed above(except the Dyson).

"I also have a Rigid shop vac with a HEPA filter(for my shop) which is actually better at dust control than the vacuums listed above(except the Dyson)."

Precisly why I mentioned it. Isn't it shameful that more companies don't improve their vacs? Same as you did with your Shop Vac,better filters can be had than those sold at supermarket. The problem has been compounded by popularity of bagless cleaners.

@AnnKH... The Aquarium will be 100x40x50. The filters will be behind the wall and not part of the bookcase and the tubes though the hole in the photo attached (this is the wall where the bookcase will be). The two doors above the aquarium are aquarium access with a height to 30cm. The bookcase depth will be 50cm, leaving 10cm behind the aquarium. This plus the space provided by aquarium access should provide ventilation and air circulation.

@HandyMac...Thank you. Would we need to apply a sort of sealant/water protection on all the bookcase wood? We planned to only do it for the section that will hold the aquarium.

That tank will weigh around 250 kg.

Will the 30 cm height above the tank be enough to easily work in the tank? I need more space than that to do water changes, move heaters, access filter intakes, and work with plants/decorations.

I would want to protect the entire bookcase from moisture - starting with ventilating the area above the tank. That's where evaporation will occur, and if you don't move the air around, it will simply condense in the space above. The small hole in the wall (which will be filled with filter tubing and power cords) will not be sufficient.

Speaking of power - I don't see an outlet on the wall where the filters will be.

@AnnKH. My husband says the 30cm is the minimum he would need to clean, change plants, water etc. What would be your recommended access height?

He's owned an aquarium the last 25 years (he actually built our current one himself), BUT none was inbuilt in furniture. So this is a new field, even for him.

How do you ventilate the area above the aquarium?

Heating: We won't be heating the aquarium. Summers are quite hot here and in winter, the temperature inside our apartment is always approx 22-25 degrees (I am originally from the tropics :)). The water temperature in our current aquarium (65x29x32) has always been sufficient for the fish.

Outlet: The filter will be behind that wall (the place out of the photo). The socket is behind there.

Thank you for all the help you are sending my way. Cheers.

I much prefer my glassed-in display shelves, but that said, most of my books are on open shelves. I hate to dust! Glass better for book life I think, based on my experience. We have one lawyers bookcase and that houses our valuable books.

I have a glass front china cabinet and open bookcases. There's dust in the china cabinet too. You might put a piece of glass on the wall to judge the reflections from an unlighted unit, could be pretty awful as you suspect.

Mock up the top of the tank and space to see if you can reach the bottom and do any sort of manipulation. I suspect 12" is fine. Allow for the light unit too.

If the tank has a good cover then not much water evaporates. Really. If you are using canister filters or a sump then you can get a pretty tight seal on the tank. Fish need oxygen so don't overdo it if using an air tight canister filter!

You will need a fan to move heat from the lighting out of the enclosure. No question about it!

I just painted my 30 year old bookcases that sat next to my 180 gallon aquarium for about half that time. Thought they were dealing just fine. Nope. No structural damage but the finish was seriously damaged. What is your plan to reduce water contact when maintaining the tank?

As for the weight of the tank mock that up as well. If you can see if the floor joists are running perpendicular to the wall that's perfect as the weight will be distributed across several joists. Get that 250 kilograms of weight on the floor, maybe several good sized people then jump up and down next to them. If there's jiggling, not good. Unsure of the weight of books and actual structure, maybe add a couple more friends before bouncing?

Nice looking project, going to be a great addition to your home.

Moisture resistant finishes are fairly simple to apply. If the natural/stained wood finish is desired, first apply a clear shellac based product. Shellac is a natural product(also used as food coatings---(think M&M's). That means is degrades as a finish, having a relatively short shelf life(not usually over 3 years). The better way to get fresh shellac is to buy flakes and make your own finish. Googling the word shellac will get you hundreds of hits and show how to mix, what concentrations to mix(one/two/three pound cuts) and how to use it as a prestain treatment and a 'primer' coat.

Thoroughly coat all surfaces of the book case pieces. If pieces are to be glued, assemble/glue first, then apply the shellac.

Then use a semi gloss or gloss polyurethane finish(usually two coats).

If you want to paint the wood, use a shellac based primer(I prefer BIN by Sherwin Williams). Do not use a stain blocking primer unless it is shellac based. Reason? You need moisture protection and the shellac based products soak into the wood more deeply than the stain blocking primers.

Then use a gloss alkyd enamel paint. That variety hardens to a very water resistant finish. I have built shelving for bathrooms with steam showers which are now 20+ years old and still undamaged.

Not much on aquariums, but I'd think a slow speed small CFM fan at the rear and an exhaust at the front would move any evaporation. Like maybe 3-4 rpm, just enough to move air.

Consider where you live and how dry the air is there. I love open shelves, but I live in a desert (Utah) where dust floats everywhere and gets into everything. If you live in a more humid area, you probably won't have as many issues with dust. Great advice above regarding how to make it work with finishes, design, etc.

UPDATE: We finally have the shelf and tank installed!! Yey! Turned out pretty great (haven't yet found handles I like though, so those are still missing). Thank you everybody for your input and advice :). ...and now on to the next project - rest of the apartment...Thank you!

@Kathy Yata...Thank you. It turned out really great...and your tank advice was invaluable :). It's a great feeling to see something one put on paper become tangible and turn out better than anticipated :).

given that the bottom is enclosed, I think it looks nice with so much open shelving above.