terrarium

Question
How can I tell if a 125g tank is a terrarium or aquarium?

Answer
Hi Jamie;

Sometimes there is no difference and they are interchangeable, but sometimes not. Glass thickness is one indication. For a 125 gallon aquarium it should have at least 1/2 inch glass. Terrarium manufacturers will use aquariums and the only difference may be the accessories, but sometimes terrariums are made with thinner glass.

If the tank is used and not new, a tell-tale sign that it was used as an aquarium is a series of white lines from mineral buildup along the top part of the tank glass. Then you know it was filled with water for a period of time and used as an aquarium and you have a better chance of being successful yourself. Just be sure the glass is at least 1/2 inch thick.  

If you decide to buy it and think the tank may have been used for reptiles or other small pets it would be a good idea to strip out all the exposed old silicone rubber sealant and re-seal the entire tank. You don't pull the tank apart, just re-seal all the joints on the inside. You can buy sealant (and a caulking gun) at hardware stores made specifically for aquariums and it says so on the label, along with "non-toxic when cured". The old silicone may have absorbed toxins that will leach out into your aquarium water and harm your fish if reptiles or critters lived in it. Will cost you a few extra bucks and it's time-consuming but worth the extra effort if you get a good deal on the tank in the first place.

At Your Service;
Chris Robbins