Cooling for Aqua One AR380

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This is my first DIY attempt / thread.

The AR380 is terribly designed. The ballast for the 11w light gets far too hot, and there's not enough air circulation. When I took it apart, the ballast was way too hot for me to touch and hold on to. Due to lack of airflow, this heat radiates down into the water through the reflector, often pushing the temperature from a nice tropical 26 degrees up to anywhere between 29 to 31 in summer.

Thus far, I had been using bits of paper to raise the hood 3-4cm above the tank and then pointed a desk fan so it would move the air in the gap between the hood and the water. This worked well, but there are a lot of issues with evaporation / temperature fluctuations / blowing atmospheric crud into the tank. So what do we do? Hack it apart and install some cooling fans! :lol: My main goal was to modify the hood but leave it looking (fairly) standard.

After I opened up the AR380 hood and removed the light / ballast / reflector, I saw that there was hardly any space in there, so I'd have to be careful with mounting. It also had terrible self tapping screws that held the reflector on, and a couple of these promptly stripped the thread as I undid them. But I was able to put them back in securely.

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So the next step was to trace the outline of the fan onto the outside of the light hood, and mark for drilling.

Then, out came the 40mm hole saw:

Not perfect, but good enough.

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I used hot glue to secure the cables inside the hood. Then used nuts/screws to secure the fans to the hood. Wasn't able to put 4 screws into each fan due to the internals of the hood. But everything is on securely, and doesn't vibrate or rattle. So I'm happy. Here is the finished product:

2 x Fans in Push/Pull configuration:

Right side of tank - air in

Left side of tank - air out

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And an activity LED (not really necessary but figured I might as well while I was there! (The ON/OFF switch is for the main lamp).

Yet to implement

- On/Off switch

- Power supply - Need to buy a power brick that outputs 12V @ ~200mA. Current draw is 124mA @ 12V.

- Some sort of grating or similar so that fingers don't get shoved into the fans

- Speed control (These are 3 pin fans, so can be controlled via PWM - If I can be bothered!)

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For the time being, I've jump started an old 300w ATX power supply for testing - looks like the configuration works well - the light has been running around 2 hours almost and the temperature is only 26.7 degrees

Next mod for this tank would be to replace the 11w light with several (~10) 180 lumen Cree or Luxeon LEDs. Will get around to that when I have time.

[Morcs]

Good work. Are you sure it needs it though? ive never had problems with the AR380 or AR320's. I usually run a 25w heater in them in find the temp to sit quite nicely at whatever I desire.

just thinking that a 300w ATX power supply turns a energy efficient tank into a power guzzler... if the fan actually helps, perhaps find an alternative method of powering it?

Other than that, room placement and reducing lighting hours should help.

Another way would be to ditch the hood entirely and use one of the clamp-on Jebo or aquaone light units, and use an internal filter also.

[SamH]

Aside from the slight overkill on the PSU, it's quite a cool little project. I might need to do the same but on a larger scale with MHs.

Good job 8)

[Jennifer]

Good work. Are you sure it needs it though? ive never had problems with the AR380 or AR320's. I usually run a 25w heater in them in find the temp to sit quite nicely at whatever I desire.

+1

On hot days my AR380 sits no higher than any of the other tanks... with or without hoods

[spoon]

i had a no name tank that used small cpu fans to cool the light ballast the power suppy was a small transformer mounted inside the hood this was rusted out when i first got the tank so i pulled apart a 3-12v multitap transformer (the kind with big black box that plugs straight into the main and has a switch for voltage) i was lucky enough that the mount fitted around the new transformer so it went straight in and i slowed the fans down a bit to run at 6v as they were noisy at 12v

http://www.jaycar.co.nz/productResults.asp?FORM=CAT

one like this will be small enough to fit inside your hood just if you dont know what you are doing get someone who does to install it it can be wired into the light switch to work when the lights are on

possibly add another one at a later date to run the leds

[Morcs]

Aside from the slight overkill on the PSU, it's quite a cool little project. I might need to do the same but on a larger scale with MHs.

Good job 8)

Surely with a bit of careful electrical DIY, the fan could be run off the same power source as the lights?

[SamH]

Surely with a bit of careful electrical DIY, the fan could be run off the same power source as the lights?

Can it be done? Someone said there wasn't a way to wire a fan into a MH ballast, perhaps they were mistaken? :-?

[spoon]

SamH

you want to wire it before the ballast i.e. using the wires going into the ballast rather than the ones coming out and going to the bulb as the bulb uses a higher voltage. for a project like that depending on what size MH you use you may be better off using a 240v fan instead of 12v cpu fans

in saying that you might not need a fan i run a 150w metal halide over my 5 ft the bulb is 30cm from the glass the glass gets warm but not hot and the back of the hood is open so air can get around it

[SamH]

150w bulb over 2ft cube fully enclosed hood, perhaps a bit out of the back. 240v fan being a household fan?

Sorry for the partial threadjack Breakaway :oops:

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As stated in one of the original post the 300w PSU is only for testing. I will replace it with a power brick from a dead cellphone or similar.

240v fans not a possibility, because the fans need to be really small in order to fit into the hood. The smallest 240v fan I've seen is 120mm.

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+1

On hot days my AR380 sits no higher than any of the other tanks... with or without hoods

Yeah, I'm sure it needs it, because without it the temperature would hit 29-30 almost every day in summer. It doesn't help that the tank is in my bedroom which doesn't get as much ventilation as any other room in the house. I'm sure all this wouldn't be a problem if the tank was placed in the living room which has a heatpump.

[Ira]

As far as a 12v supply for the fans, if you don't have a 12v wall wart laying around how about a 50w 12v halogen lamp ballast? They should put out 12v(One would imagine ) and you won't come anywhere near its capacity with a couple of fans. They're pretty cheap too, I picked up a 110w one for $14.

If you wire it into the mains plug that powers the lights and can hide it in the hood it could give you a much tidier installation than having a second wall wart plugged in alongside the lights...Cut down on spaghetti a bit.

[spoon]

good idea ira except a lot of them are 12v a.c

a $2 bridge rectifier would fix that though

[Ira]

good idea ira except a lot of them are 12v a.c

a $2 bridge rectifier would fix that though

Ah, yes they probably would be wouldn't they? Where's the facepalm smiley?

[SamH]

Where's the facepalm smiley?

and/or

8)

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I want to keep power for the cooling separate as I have to install the LEDs soon, and I don't want to tie anything into the current ballast / wiring. I'm not very comfortable working with mains voltage either

[matthewY]

nice pics and good idea with the Leds, been looking at something similar but too scared to cut holes in my hood.... 10mm 220,000 mcd leds should do teh trick and keep it pretty cool...