What to Use to attach Plexi to Plastic????

[sphelps]

I assume the tank is glass with a black plastic brace around the top. You removed the black plastic center brace and are looking replace it with clear. Best solution is use glass, have it cut to fit exactly from inside front pane to rear pane (same length as side glass panes). Install the glass brace with silicone underneath the plastic brace so you have glass on glass contact. This will be the strongest. Another alternative is to remove all black plastic trim on the top and Euro brace the whole tank, this eliminates the need for a center brace all together.