TEOPICAL AQUAEIUM FISHES 217 



(The foregoing mixture of gasoline-paraffine will waterproof wood, 

 concrete, brick, fabrics or anything that will absorb it. For fabrics to be 

 used or bent, use only one ounce of paraffine.) 



After making one of these aquaria the knack becomes very easy. 

 A row of them of uniform size presents a neat appearance and can be 

 used in small space, since there is no projecting base. This style of con- 

 struction is suitable for aquaria with bases up to eleven by eighteen inches. 

 In larger sizes the uprights and top angles ought to be from five-eights to 

 three-quarter inch metal, while heavy wire screen should be embedded in 

 the cement for re-inforcement. 



If the frames are to be nickeled this should be done before pouring 

 the cement base. 



Glass for Aquaria. Although double-thick window glass may be 

 used for aquaria up to the 25 gallon size, plate-glass is so much hand- 

 somer and costs so little more, it seems like a wise investment. If- window- 

 glass is used, the imported kinds will be found best. Plate-glass is now 

 made in 3-16 inches thickness. This is suitable for aquaria under 50 gal- 

 lons. For those for 50 to 75 gallons, the best thickness is % inch, and for 

 the still larger sizes up to 120 gallons, y^ inch. The author and others 

 have occasionally picked up bargains in plate-glass from plate-glass 

 insurance concerns, who often have on their hands large remnants of 

 bulk-windows. 



Setting the Glass. The edges of the glass should be carefully 

 cleaned with whiting, ammonia or alcohol to remove any grease. It is well 

 to first coat the edges which are to come into contact with the cement 

 with gold size, allowing this to set for a day or two. This is more 

 particularly needed with large plate-glass aquaria. Apply a liberal coating 

 of aquarium cement to the inside of frame, and a thin but well covered 

 coat to the contact edges of the glass. Press into place slowly but firmly, 

 cleaning away at once all surplus cement. Light sticks cut of a length 

 to brace across inside of aquarium will maintain an outward pressure 

 on the glass for several days until it is fairly set. After the glass is well 

 set it is advisable, especially with the larger sizes, to run a line of aqua- 

 rium cement up the inside corners and along the bottom edges, covering 

 with a narrow strip of glass, or. better, embedding a glass rod of from 

 ^ to ^-inch diameter in it, pressing in as far as possible and wiping 

 away the surplus cement. 



Fill slowly in about a week and change water several times in two 

 weeks before putting in fishes. 



Large aquaria nearly always leak a little at first, or after moving 

 them, or even after emptying without moving. This usually corrects 



