Top Vs No Top on reef tank

[georgiaboy013]

I had always ran a open top reef tank until about 2 months ago when I got tired of fish carpet swiming.......Ok I was losing almost a gallon a day in water , Now I don't hardly lose any water and still have all my fish even the one that has a little carpet burn spot on his side........
what is everyones idea on open top Vs Closed top

 

[georgiaboy013]

Sorry....ment to say my tank system came with a fitted glass top

 

[nickskains]

Having it completely closed off with a glass top does restrict gas exchange from the tank. Granted you won't evap as much water. There might be other reasons why having it open or closed is better or not. I am just unaware of them.

 

[xyzpdq0121]

Glass tops also filter out light from that $700 halide system that you bought..

 

[hdfisher]

Where can you purchase eggcrate? LFS?

 

[jason sartain]

I don't have a top on my 240,but everything else does.

 

[derek_s]

I love the look of open tops, but ue to jumping fish and the desire to use t5 lighting, I built a canpy that is sealed with plastic msquito netting.

 

[lees]

I had a fitted glass top on my 20L that came with it. It really helped with water clarity I guess but the gas exchange is what I I was worried about in such a small setup. Fortunately I stepped on it and broke it which has left me topless. I seem to get what appears to be dust in the tank on my LR but I blast it with a turky baster and suck it out when I do w/c's. I prefer topless but I can see where jumping fish would be of concern.

 

[george]

dawgdude;248747 wrote: however egg crate cuts PAR down BIG time

Do you have any figures on this or recolections of ballpark percentages? I'd expect it to cut some (it is a technically called "lighting diffuser", so I'd think it'd scatter some), but is it that pronounced?

By the way, if you get a nice blank look at your Lowes/HD from the staff, ask where the drop ceiling and ceiling tiles are. That's where they have eggcrate. Sometimes it's the next isle over from the lighting section, sometimes it isn't.

 

[george]

ares;249844 wrote: eggcrate is white and should reflect most if not all of the light it would otherwise block.

But the surface area that would be at a reflective angle away from the tank is quite small. Really just the total surface of the 1mm or so thick tops of the bars. Most reflection off the larger white sides of the cells would go into the tank.

However that assumes perfect reflection which would defeat the point of a diffuser, so there still may be drop off. I'd like to see some numbers. Perhaps the silver eggcrate would solve this problem.

 

[george]

Seems some experimenting by people bears out what I suspected:

http://forum.marinedepot.com/Topic24384-13-7.aspx">http://forum.marinedepot.com/Topic24384-13-7.aspx</a>
[IMG]http://reefcentral.com/forums/showthread.php?threadid=426618&perpage=25&pagenumber=1">http://reefcentral.com/forums/showthread.php?threadid=426618&perpage=25&pagenumber=1</a>

The exact impact seems to depend on your lighting type and arrangement, but the contention that it lowers PAR greatly overall doesn't seem to agree with experiments.

Still, the best arangement would be a good canopy for lots of reasons, but that's not always possible.