How to keep divider in place without scratching tank?

[Kollection]

I just bought some egg crate to divide my ever growing collection of flowerhorns because they seem to be the cheapest solution. My question is how can i keep the egg crate divider in place using suction cups? I have those plastic divider sheet holder suction cups but they only fit sheets a few millimeters wide. Egg crates are way too wide to fit in between the slot. I really don't want to cut the egg crate to the exact width of my tank and force it into a tight fit. My tank is plexi and I don't want to scratch it, that is why i rather cut it shorter and use suction cups to hold it in place. Anyone have an idea what i can do?...or do they sell holder suction cups that fit the width of an egg crate? any suggestions welcome

 

[Miguel]

Put heavy rocks on both sides of the divider. Put them in a position that the dish cannot move the divider by pushing it.

 

[surfpalmsncycads]

no worries. zip tie suction cups to the eggcrate i do it all the time.

 

[Darsie]

Jam cut up bits of airline between the divider and tank if the dividers abit smaller. i've never tried it with larger fish though

 

[Kollection]

good suggestions, thanks guys