i sometimes see on the forum, questions about or help to find tank dividers, which usually means egg creates or similar. i thought i would post my diy option which is cheap, removable and also keeps your fry separated within your tank.
i use 5mm “corflute” which is a hollow plastic sheet, fly screen (fiberglass not aluminum) and some fish tank friendly silicone. (bunnings or similar has all this in stock) it cost about $25 to make 6 dividers for my four foot tanks and took about 1.5hrs.
the construction is as follows:
mark out your corflute. make sure you allow 1 or 2 mm wider than your tank, so when you insert it flexes and therefore remains in position. the size of the fly screen cut outs is up to you, i allowed about 50mm around the outside which gives a large open area for water flow.
cut out all your pieces using a stanley knife. i did it on a piece of cardboard in the garage so the concrete floor does not blunt your knife.
using the waste from the inserts you will need to cut out strips, maybe 30mm wide. these strips are used to neatly hold the fly screen in place.
cut out your fly screen wider than your cutouts. 30mm larger on each side is a good amount.
silicone it all together.
1. lay a bead of silicon around your cutout
2. place the fly screen over the cutout out
3. place 30mm strips around your cutout to hold the fly screen in place.
i used selleys glass silicone sealant which is fish tank friendly. make sure you cure it for the recommended time before you place it in your tank.
finished item in the tank. i hope this give you another option for dividing your tank.