Running Mh's Over A Wooden 'hood'?

[thefirethief]

Hi there, jumping fish question here. When faced with this problem with some freshwater fish I was told that fish jump at an acute angle from the water so the best way to solve the problem was to lower the water level by 3 or 4 inches. This makes sense however however as I'd like to maximise my water volume in my 30Gal reef I'm considering building a hood with no lid that would effectively raise the edge of the aquarium above the water by 6 inches and still allow me to run MH's over the water. I've got 2 quick questions...

Will it be a problem running the MH's so close to wood?
Will the height of the new egde round the tank be effective in stopping reputable jumpers such as Jawfishes or does the tank need to be pretty much 'sealed'?

Any advice would be lovely.
Mark

 

[SkiFletch]

Well, I've watched my wrasses jump 8-10" with no problem during feeding time, so I'd go more like 12-14" with your open-topped hood plan. And yes you can run halides that close to wood. Just employ a fan or two to keep heat warping to a minimum. I have dual halides in my sealed hood with four fans and it works great

 

[thefirethief]

Thanks skifletch, that sounds easy enough although I might need to re-think things if I'm going to have to install fans. What are the noise levels like? My tank is in a bedroom so would need to be as quiet as possible. I'm already having trouble with the Tunze 9002 I installed a few weeks ago. You can hear it at the other end of the house sometimes.

 

[SkiFletch]

With an open-top like that I'd suggest just a couple 120mm low-rpm fans pointed at the bulbs or even hung off the sides of the reflectors. These fans are common in DC electricity (needs a power supply) for computers, and in AC electricity for eletronics and process control cooling. I prefer the aluminum AC models myself as they tend to be much quieter. Generally the ones from 2000-3500rpm are virtually silent and more than enough air for the job . The 120mms have a large enough blade size to push air and still be quiet

 

[thefirethief]

Thanks again skifletch. I've had a look at the very fans you are talking about although I'm not good with electronics so I'm unsure how these fans are actually powered? I've also just had a look through pictures of your beautiful new tank and the hood setup seems exactly what I would need.

 

[thefirethief]

Just been skimming through the forums for a while here and have just found the answer to the above question thanks to BigC's nano journal. Do the fans really make a difference without vents? Surely its still just hot air moving around which (I assume) won't have much effect on temperature?


Ta, Mark

 

[SkiFletch]

Well mark if you look at my new hood in my new journal, you see the 4 big fans in there. Mine are A/C electrics which means I just wired them all straight to the main +/- A/C of my house. You can see the terminal block there. All 4 ones on the left are my A/C black wire and all 4 on the right are the A/C white wire. If you get D/C powered fans, you have to use BigC's methods for wiring.

Anyways, I have 3 fans positioned to blow air from the outside to the inside, and one fan positioned blowing from the inside of the tank venting out. So the hood is slightly positively pressurized but vents a lot of air. If you put your hand behind the exhaust fan you can feel the heat coming out

 

[thefirethief]

Got it! Thank you sir!

 

[AK77]

You could also use egg crate or a similar mesh that will prevent fish getting out, but will still allow light in and the water to evapourate to aid cooling.

 

[thefirethief]

Cheers AK77, I have been considering that too as I wouldn't mind buying one of the arcadia series 4 pendants or something similar to hang over the tank. I assume I couldn't mount these in a hood so the only other way to cover the tank would be egg crate however I'd be a bit concerned about cutting any light, however minimal, to the tank. Do you think this is a foolproof way of stopping jumpers? I've heard a few stories and this jumping jawfish thread seems to sum things up.

I think I need to 'get the finger out' and just go for something. Either start my custom hood, which would be a fun learning curve which could potentially fail miserably, or go the eggcrate way.

Mark

 

[SkiFletch]

Narry a wrasse ever escaped my old egg-crate covered hood... Works wonders and barely cuts down on light IMO

 

[thefirethief]

Cheers skitfletch. Seems like a much simpler solution to the problem, and I can always upgrade later once I get to grips with a few things. I've got some LR coming tomorrow so I'll take some pictures of whats going on so far and put a thread up in the journals to show the progress. All very exciting.


Mark