What sort of cover should I use?

[Kryos]

Originally Posted by mrhasan

That's something that concerns me too. I haven't read anywhere about mesh getting salt creep but egg crate accumulating salt creep. This is causing a pain in my head

From my observations, Salt creep comes mostly from bubbles popping at the water surface, if you have lots of that, you're going to get salt creep regardless of what you put on top of your tank. For my 20g with all hang on skimmer + aquaclear, I get bubbles from when the water falls back into the tank, I see tiny drops of water fly around from the popping bubbles when I take my glass cover off and the salt creep on my glass cover for that tank is a huge pain.

However, for my 5g zoa/ric tank with egg crate on top, I have no bubbles popping near the surface (as there is no equipment other than a powerhead) and there is no salt creep at all.

Now from my personal experience with Eggcrate, it does reduce the light somewhat but what bothers me the most is the grid shadow I get on my sandbed as my 5g is only 10" tall.