Timing of the lights

[fishgoogle]

I would like to find out how often do we switch on the lights for the planted tanks?
The consideration I have is as follows;

1. To switch on the lights Continuously for long hours, it will heat up the water. Therefore if we time it maybe at a 3 to 4 hours interver, it might help to reduce the heat.

Can someone share your experience?

Cheers!

Fishgoogle

[vinz]

Technically yes, having the lights on at intervals will help reduce heat buildup.

The problem is how it effects the plants. Plants do have a day-night cycle and they do suffer if we break it. This means you have to limit the intervals to the 12 hours of it's day (be it natural or simulated by our artificial light). Since this method does not give the plants consistent light, they will not grow optimally. This in turn might lead to algae having a upper hand.

So far, in my experience, the temperature of the water will rise about 4 degrees, from 28 celcius to 32 celcius with the lights on. How fast does this happen? Assume, for example, it happens in an hour (and assuming the rise is almost linear for such a small change). To prevent it from getting to 32 degrees, we turn off the lights after half an hour to allow the water to drop from 30 to 28degrees again. That will take about half an hour, after which we turn on the lights again and repeat the process.

The lights will only be on for half the entire 12 hour "day" period.

[|squee|]

I switch mine on for 10 hours, and I use a set of two computer fans running at the same time to reduce the temperature.

Turning lights on and off at intervals will be detrimental to plants, like vinz said, and the light set too since constant switching on and off will cause wear and tear to the set.

[baranne]

I also switch mine on for about 10 hours. To reduce the rise in temperature, I raise the height of the lights so that there is a bigger gap to the water. I also have a DC fan running 24hrs.

[confusekid]

Mine is on 12 hours, I have 2x 5 inch AC fan on 24hour to cool the water.

[cairocks]

I am playing around withg my 3X36PL lights. Total lighted period is around 10.5 hours but
1st 45mins 1X36W,
then followed by 3.5 hours of 72W,
then 30minutes of 108W
then reduce to 36W for 1hour to simulate overcast sky
then back to 108W for 45 mins to simulate noon
back to 72W for 3hours
and lastly 36W for evening sky for 45 minutes followed by lights off.

Had been experimenting with this regime for 2 weeks. Find that the bba seems to be reducing. Dunno is the reginme working or the new SAE is doing its part.

In the past had been using progression to 108W then reduce back to 36W over 11hours but bba start appearing so trying out different combinations.

Quite complicated combination, still playing around with the timers.

[Rupert]

Quite complicated combination, still playing around with the timers.

What sort of timers are you using? As I find the ones that I use [depressed levers/portions mean on, raised portions mean off] leak time and start earlier and earlier. I have been thinking of finding some electronic ones

[cairocks]

What sort of timers are you using? As I find the ones that I use [depressed levers/portions mean on, raised portions mean off] leak time and start earlier and earlier. I have been thinking of finding some electronic ones

Using 2 mechanical ones bought for the lights and 1 digital one for the CO2 all bought from carrefour. So far pretty accurate. But got a mechanical one that is not used one cuz it won't turn on automatically but will turn off automatically. Dismantled it to adjust, worked for 2 days and then back to the same fault.

[rally]

I turn on only abt 7 hrs a day to control agae growth.

[rally]

the other factor that I tou of is convient, cos I work in the day and is only night that I get to see the tank, I turn it on (timer) only at 5pm till 11pm. It work well for me so far

[baranne]

Did not know that the mechanical timer will leak time. How long before this problem will surface?

How much is the digital timer?

[vinz]

It probably depends on the brand too... so you should ask, which brand/model of mechanical timer too? I've been using TheBen which has been on time so far.