What is a cover glass and how does it fit?
April 15, 2009 by admin
Filed under Fish Tank Supplies
A cover glass is an aquarium cover. It is best made of light plate glass so as to be more break-resistant. When used with a reflector, the glass should start from just behind the reflector and cover the balance of the tank. Under no circumstance should the cover glass be extended under the incandescent reflector. The heat of the bulbs is likely to crack the glass. Also, the glass coming between the light and the tank may filter out a good deal of the light and retard plant growth. With a hood, no cover glass is necessary.
The rear corners of the cover glass may be cut out for a heater and/or filter. There are clips and handles available which can be fastened in place to suspend the cover glass inside and just below the rim, rather than having it rest on the rim of the tank. These are helpful because they prevent moisture from gathering between the glass and tank rim and corroding it.
When neither reflector nor hood is used, a cover glass should protect the whole aquarium. The functions of a cover glass are many. It helps regulate the temperature, prevents fishes from jumping out, reduces evaporation, keeps out dust and dirt, and also keeps out inquisitive fingers and paws !
For a tank kept in a sunny or extremely light location, the cover may be of translucent glass to cut down the glare.
For proper aquarium heating, you need a source of heat that can be regulated. The heat given off by the reflector is incidental. Most people turn their reflectors on in the evening when the house is at its warmest and turn it off when they go to bed. Should they be dependent solely on the reflector for heat regulation this would result in the tank temperature being at its peak during the evening and plunging rapidly down during the night, when the light and usually the central heating system are both turned off. This could be disastrous. Unless you are prepared to keep a close watch on your tank thermometer, turning on the light as the temperature drops and turning it off when the heat rises, you cannot depend on the reflector. Actually, you would be turning yourself into a thermostat. It is much more practical to buy one.
