Glass or no glass...that is the question

[SittingDuck]

I've got a 5 month old FOWLR with one colony of Button Polyps (I Plan on adding more corals eventually). I have a light fixture that is on legs that stands 2 inches above the water and had to replace the Canopys that came with the tank due to the amount of light they would block. Right now, it's an open top with nothing over it.

A few days ago I had a Longnose Hawk jump out of the tank. I found him in the morning stuck to the carpet. I've also had a Firefish jump out of the tank also.

I was speaking with a guy at my LFS and mentioned that I was considering getting a glass lid for the aquarium to stop the fish from hopping out. He said it was a bad idea that the glass top would stop %40 of the light and was bad for any reef aquarium. He said that the jumping fish were an acceptable risk for any reef aquarium.

I was trying to consider other options because I don't like the idea of jumping fish, regardless if it's acceptable or not, and was wondering how a screen, similar to the kind that is used on a screen door, would fair over the top of the aquarium? Is there any way to put anything over the tank to stop the jumpers, yet allow the maximum amount of light to pass through to not upset the corals? Or are jumping fish an "Acceptable risk" when trying to setup a reef tank? Is there a natural way of preventing the fish from jumping? Say, surface agitation that would keep them from the top (2 or three power heads skimming the surface for example)?

Thanks.

[hackteck]

have you considered eggcrates? their sold at home depot

[SittingDuck]

That's a good idea and will look into that...

I'm also having a major issue with evaporation since removing the canopy. Previously, I'd have to top off the tank once a week (I would coordinate this with my weekly water changes) but since removing the canopy I have to top off two to three times a week. I did a water change on Thursday, went away for the weekend and came back Sunday night and it looks like 6 gallons of water has evaporated!

This has been wreaking havoc on my salinity (Water evaporates, Salt stays) and I've been battling to keep it within the 1.025 threshold (It's usually up around 1.026 to 1.028 due to evaporation).

Does anyone have this issue also? Or have any way of battling this? I've considered an automatic Kalkwasser top off, but I don't think the additional Kalkwasser will be able to keep up with the amount of water that is evaporating.

Thanks.

[hackteck]

i usually loose 1 to 1 1/2 gallons a day to evaporation

[tecwzrd]

If you do decide to use a screen get one designed for the purpose to handle the heat from the lights. I wouldn’t use glass tops since they tend to make your tank build up CO2 and cause negative fluctuations in O2 and ph.

For top off I’d use an auto top off hooked to the sump or main tank and pumped from a reservoir of ro\di water.
This one from premiumaquatics.com is only $60


3 other suppliers of for this switch.
ultralifedirect.com
thefishdepot.com
petsolutions.com

[localhost]

Not an expert but I use a AGA Twin-tube versatop. It does block some light, but %40 sounds like a bit much. As far as CO2/PH problems, I think as long as you have some open air exposure to the tank water (sump), you should be fine.

[SittingDuck]

Unfortunately, I don't have a sump at this time, but looking into getting one custom built. My stand has odd measurements which makes finding a sump very difficult (22" width, 16" depth, 26" high).

Is there any way that I can stop the fish from jumping without adding a lid of any kind? The guy at the LFS mentioned that if fish start chasing each other they'll jump out of the tank. I've got 3 Damsels in there and one of them is a little pesky to other fish around his size (Constantly chasing the other damsels). Has anyone heard of fish jumping to escape other fish or am I misunderstanding what he's saying?

I've been looking into an auto-top of drip system for Kalwasser (Which I'm not using at this time, but will be soon) so maybe I'll step up the timeline on that one.

Thanks for your comments and suggestions!

[tecwzrd]

Most fish will be content to stay in the tank irregardless of being chased or not. That said just about any fish can potentially jump out of an open tank for any reason and your best bet against that is to choose fish that are not known carpet jumpers if you continue to keep going topless. Damsels are pretty safe to keep topless.

The Longnose Hawkfish is a tank jumper and requires some sort of cover to keep them in. It doesn’t mention this on liveaquaria.com but they don’t always mention it except for the species that are always known to jump or escape. For example the Yellowhead Jawfish is known to jump when startled or frightened.

Before any fish purchase I would review several profile sites to make sure before buying.