The following is a step by set how-to for making a mesh lid for those of us with open top tanks. I have always liked open top tanks with hanging lights for ease of maintenance and heat dissipation, but of course, the downside is that certain species of fish, wrasses and gobies come to mind, can jump out of the tank because they don't have the safety a canopy provides.
I own a standard AGA 210 gallon (72” x 24” x 24”) with top trim, and a custom 100 gallon rimless (30” x 30” x 24”).
I have several Hawaiian Flame Wrasses in my 210 gallon, and a wrasse and 12 scissortail gobies in my 100 gallon, and the reason I made my screen cover was for them. I lost a couple scissortails to carpet surfing
These clear mesh tops will work for tanks with top trim and tanks that are rimless. I have a set of instructions for placement on rimless tanks as well, located towards the end of this DIY. I know that a mesh top somewhat defeats the aesthetic purpose of a rimless tank, but whether you place one on your tank depends on what fish you have and how likely they are to jump.
So here is how to do it:
Step 1. Pictures of my 210 and 100 gallon tanks. You can see the carpet surfing potential there.
Step 2. Gather your materials. For anyone that has installed or replaced screening this is a no-brainer. You can source everything at Lowes Home Depot, or any local hardware store You need the appropriate length of 5/16" screen frame, plastic screen corners, plastic screen corner pieces, .140" screening spline, and spline installation tool. Total materials cost to do my 210, except the clear mesh netting, was about $15
You also need to decide what type of netting you will use. I have found that the best type, considering the factors of light blocking and opening size, is a clear ¼” square opening, polypropylene mesh. This is the best choice because it allows light penetration, but the opening is small enough to keep small fish like gobies and small wrasses, in the tank if they jump, and since it is 100% polypropylene, it is reef safe. I had to buy a large roll of the stuff, as it is very hard to find in small quantities.
Step 3. These are the 4 sections of screen channel I cut for each of the openings I made a cover for, and the plastic corner pieces.
Use the instructions on the plastic corner pieces for proper measurements. I used a hacksaw and a miter box. The pieces are simple butt end cuts. The plastic corner pieces are really handy. I determined total length of the inside lip of each section of the 210, then subtracted 1/8" so each cover would go on and off easily.
Step 4. The corner plastic pieces slide into the channel frame. Nearly idiot proof, as they only go in one way.
Picture of the finished frame assembly.
Front:
Back
Step 5. Pic of the back of the frame. I have 4 Tunze 6105 pumps for circulation, so I used a dremel to edge out an opening on the back of each frame to allow the power cords to pass. You may or may not need to do this depending on your setup. The frame piece is still strong, even after removing that much material.
Step 6. Mesh netting installation with spline. The spline material goes into the channel and holds the clear mesh netting. The spline tool is used to push the spline down into the channel. Start in a corner and work your way around all 4 sides. When you make the covers, just don't stretch the netting too tight as you install the spline, because it can bow the aluminum channel inwards, and make the cover not want to lie flat. You want to keep even tension on the mesh as you push the spline into the channel, but not too much tension.
Example of spline installation without the mesh:
Spline being installed with mesh.
Completed spline installation.
Step 7. Trimming the excess screen material away from the frame. I used safety razor blades to trim the excess screen material. You want to work carefully, and cut on the OUTSIDE part of the spline on the side of the channel. This gives you a very clean look. This section is face down, so you don't see it anyways, but a careful trim job here allows the cover to lay down flat on the inner lip of the tank. It just looks better.
Completed trim job on screen, bottom side.
Completed mesh screen top, right side up.
Step 8. Install on your tank.
210 gallon
Another top on my 60 gallon cube.
Rimless Instructions.
Please follow the regular instructions, except you need to make the mesh top to the outer dimensions of your rimless tank, meaning the total length and width of the tank, including the glass. This is because the mesh top will sit directly on top of the rimless tank.
Here is how I have my mesh top sit securely on my rimless tank.
Step 1. I cut out two thin pieces of acrylic in the shape of a capital “L”. I then bent each one as you see in the picture below. These were siliconed in place on the back left and right top corners of the left and right glass panel as seen in the picture below. These two pieces hold the mesh top in place when you replace it after feeding or tank maintenance.
Step 2. I cut two small pieces of acrylic and siliconed them onto the front left and right top corners of the front glass panel. See picture below. You may need to play with size, as these should be cut to fit the hollow underside of the mesh top front corner pieces.
The plastic corner pieces of the mesh top are hollow on the bottom, and the screen top front left and right corners fit over the small plastic pieces siliconed on the front corners of the front glass, and they serve to keep the mesh top in place as it sits on the tank.
Completed top on 100 gallon rimless tank.
I fabricated plastic handles for the screens on my trimmed tanks to make the tops easier to remove because they slip in pretty flush in the glass channels on my 210 and 60 gallon tanks. The rimless does not really need one.
That is about it. If anyone has any questions, please feel free to send me a PM via the messaging system here.
Best regards,
David
