Hi All,
I'm new in this forum and quite new fish keeper as well.
I want to upgrade to a bigger tank now and was thinking about getting Fluval Osaka, as the design is stunning and I simply love it.
The only problem I can think of is lack of the lid.
Does anyone have any experience of that?
I'm not worried about fishes jumping out etc - what worries me is the high level of water evaporation due to open top and the amount of pollution that might get into the water (dust etc.).
I've read that some people were trying to fix it by ordering cut to size sheets of acrylic or other plastic materials - but does it really work? If the length of the aquarium is more than 100 cm - I’m worried that the plastic might bend under its own weight.
I’d appreciate any advice.
Many thanks.

I ran a tank with no lid for about 8 months, so i think i can shed some light here
You shouldnt have a problem for the most part but there are a few things to think about. Where is the tank going to sit? Are there any dangers of things getting put in the tank or possibly falling? (a bottle of babies milk can ruin your day/week once its in your tank to speak from experiance)
I wouldnt personally worry about dust too much since you will have filters to handle it.

On the topic of the DIY top,if you decide to make a top i would reccomend glass, the plastic may be able to stand the weight of its self but i doubt it would live up to the constant light source right above it, between the light and its weight i think it may destroy its self.

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It has become more than a hobby! My 29gal Dream Reef DIY Build

A quick fix until you can get an upgrade is cut a piece of cardboard that fits your tank, wrap it in tin foil, and if you have lighting needs, cut out a big hole the size of your light and glue on some plastic wrap

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55gal ~ Freshwater
90gal ~ Saltwater
100gal ~ ?

With no lid you'll have to top up more often but that's not a big problem. I'd still say it mostly depends on the fish you plan to keep. Some fish are jumpers and there is no way you can have them without a lid, with others there is not much risk.