Raising height of light

[nigel bentley]

Getting a little bba on my 400 litre low tech tank
Satisfied with filtration, water parameters,water temps,stocking,feeding plants and fish.
I believe my problem could be lighting
I have an led strip light which covers approx 1200mm of the 1500mm tank length.Lighting duration is short only 51/2 hours daily
My light doesn't allow and modifications
I was wondering if I can decrease the light intensity by increasing distance of light to water surface.
I have a clear perspex lid and the led light sits on top.It currently around 4 inches from surface of water
I was thinking of doubling this to 8 inches by rasing the light.
Incidentally,the portion of tank with less light seems algae free at the moment. Sorry for long winded post,but any thoughts would be gratefully received.
Thanks
Nigel

 

[PARAGUAY]

Raising it would be good move. Then observe to see whether it improves

 

[nigel bentley]

Thanks for your reply,I will give this a try out. Going from high to low tech, the light is the only thing ,I haven't changed so hopefully decreasing light intensity is the key.
Tank is quite heavily planted now and I'm using hydrocotyle leucocephala as a floating plant which will hopefully help with the light.
Also doing with APT zero as I have fish which do provide some nitrate.
Thanks again
Nigel

 

[ian_m]

Rather than raise the LEDs

• Put either darkened plastic sheet in front of LED's.
• Strips of foil across the LED's to say block 1/3 of them.
• Get a dimmable LED supply ?

 

[nigel bentley]

Hi Ian, Thanks for the suggestions. I like the sound of darkened plastic sheets. I'm trying wooden blocks to raise height but may resort to sheets.
Getting a dimmable LED supply, does that involve getting a new light or is it something that works with my existing?

 

[Simon Cole]

I have used a Perspex Neutral 9T20 lid to reduce lighting. The aquarium I used it on was 90*30*30 cm and had 4 high output T5 fluorescent bulbs. It seemed to do the trick.

 

[MartyK]

Fiberglass window screen is also an option to reduce lighting and it comes in convenient and inexpensive rolls. It was common in the olden days of the saltwater reef community to use a couple layers under metal halide lighting when you were acclimating new coral, or new lights.

 

[KirstyF]

Grey plastic mesh, the type you would use for a fly screen, is another option, super cheap and surprisingly effective. You can use however many layers you think suitable to reduce light.

 

[ian_m]

Getting a dimmable LED supply, does that involve getting a new light or is it something that works with my existing?

Yes you can get LED drivers than take a 0-10V input, from a potentiometer to control the brightness.

Some LED drivers have an inbuilt potentiometer, you twiddle with a screwdriver, to set the brighness.

 

[Wookii]

Getting a dimmable LED supply, does that involve getting a new light or is it something that works with my existing?

What is the existing light? Does it have a separate power 'brick' transformer? If so, just check the voltage shown on it - chances are its 12-24 volts, so a controller like this should be suitable:

Amazon product ASIN B0BM93NQL7
There are a fair few other choices on Amazon.

 

[nigel bentley]

Hi Ian,
The light I have is an Aqua One J bar,66 watts.It plugs straight into a 240v socket and the lead has a sort of disconnecting point in the middle(sorry, I don't know correct terminology)🤷‍♂️

 

[Wookii]

Hi Ian,
The light I have is an Aqua One J bar,66 watts.It plugs straight into a 240v socket and the lead has a sort of disconnecting point in the middle(sorry, I don't know correct terminology)🤷‍♂️

From the little I can see online, it looks like the light uses a 12v transformer, but the built in electronic timer module might interfere with an external controller. It depends on the lights behaviour when power to it is cut.

 

[nigel bentley]

Thanks Wooki.At the mypur ment, I'm using some offcuts from a fence post with some photos to hide them.
My wife hasn't complained so all good 😃Thanks for all your help