Are Legos Safe For Aquariums?

There are 75 Billion Bricks Of Legos Sold annually in 140 Countries. Legos are very popular nowadays as well. So it raises the question of are legos safe for your aquarium. In this article, we will dive more into legos, plastics, and more you may want to know.

Yes, LEGO@ has announced that they are indeed safe for aquariums. The LEGO Bricks are comprised of hard durable plastics which make them safe for your fish tank.

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Knowing this it still would be a good idea to keep loose, floating LEGO@ bricks away from your fish in case they try to swallow them because after all if they can swallow them then they would.

Before considering placing your LEGOs in your fish tank I would consider sanitizing them as recommended by the manufacturer.

I’m sure you may also be cautious of the paint am I right? I bet the paint for LEGOs is still much better quality than fish stores. I would trust the paint quality.

How To Make Sure LEGOs Do Not Float In Your Fish Tank

Is Epoxy Resin Safe For Aquariums

Super Glue IS;

  • cheap
  • easy to use
  • longevity is fantastic
  • has a stronghold

Safe for fish?

  • BPA
  • Algae Build Up
  • Small Openings
  • Aeration

BPA Chemical

Best Plastics For Your Aquarium

  • #2
  • #4
  • #5

The #2 HDPE (high-density polyethylene) plastic is one that I would consider good for your aquarium. But, I would still double-check just to be safe. You will know if it is food-based plastic if it is marked FDA or NSF Approved. #2 plastics are milk jugs and also plastic buckets.

The #4 LDPE (low-density polyethylene) plastic is one that you can use in aquariums. But, just like #2, I would double-check to be sure since it is your fish we are talking about. Every company should have a section on their website or customer service that can answer your question. #4 plastics are shopping bags, store bags, juice box labels, and milk carton labels.

The #5 PP (polypropylene) plastic is also safe for aquariums. The #5 plastic is ideal for hot liquids since it has a high melting point. #5 plastics would be baby bottles, kitchenware, plastic cups, and microwave-safe containers.

Algae Build Up

Not all the bacteria associated with algae are bad. In fact, there are beneficial algae that are at work as well so if you want to clean the decoration I advise doing it one at a time so you do not kill the beneficial bacteria.

Small Openings


Do Legos Float On Water?

However, if you would like your legos to sink, like a sunken pirate ship, this is a good call. I would recommend that you consider adding some type of sediment on the bottom or inside of the lego decoration so the current will not move your legos around.

LEGO Fish Tank Decorations

Now it’s the fun part. I love seeing different decorations for other fish keepers. It’s interesting to see what others come up with for their own aquariums.

Some of my favorite ones that I enjoy seeing are ones with cities built on top. The plant escapes are good with much more foliage from the plants so I’m not sure if the sunken submarine would be one that I would personally go with.

This Mario Decorated tank is absolutely awesome. Personally, I enjoy the old-style retro games so this is a very cool setup for small fish like neon tetras. The castles are very well structured LEGO bricks but I do not think the rest are LEGOs. Most likely just placed to fit the design.

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