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Is there any rule of thumb for lighting wattage for low tech.


12 Nov 2009

I'm back again, it's been a while. I'm setting up a low tech tank here in Vietnam. Back in the old days there used to be solid Watt/Gallon rules for lighting, but with the advent of LEDs I'm not really sure how much I should be going for with a low tech tank. I have a ~400L tank, so just wondering if anyone has and advice on the right level of lighting for this EI Natural Low Tech setup.

Still very work in progress:


That's 3 x 20 watt LEDs but no idea if that's about right.


Hi @Stickleback Hard to say what the advice would be for a blackwater(?) tank like this - they are usually fairly dimly lit - and it will dim even further when more tannins is released from the wood. I suppose your going to go with some hardy slow growing plants? such as Anubias and Bucephalandra perhaps... They won't be needing much light really. The light you have now seems fair, but I would add some floating plants to provide a bit of shade right below the "bulbs".

I am sure someone else can add to this.

I like the setup btw. What are you planning for livestock?

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Best advice is to use dimmable lights, or those that can be raised or lowered to adjust intensity according to close observations of plant health and growth and the appearance of algae.

However, overall light intensity will need to be much lower than in a high-energy CO2 injected tank. The advice to use floating plants and plants that grow leaves across the surface Is sound too.