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Please help me choose right Flood light for 20 gal tall tank

2212 Views 4 Replies 2 Participants Last post by  mihzyd77

My first post. I have a 20 gallon tall tank it is approx. 24" wide x 12" deep x 16" tall and I'm looking to place 2 either 10 watt or 20 watt LED flood lights for a freshwater aquarium that I will be growing plants in using the Diana Walstad method so no chemicals, no Co2 etc... and looking to have Med-High lighting and may little high where moss at very bottom of tank can flourish as well. I plan on putting plants in my tank that is recommended in her book which I can't recall the names now with about 10 fish ranging from Sunset Gourami, 3 ghost fish, 1 pleco, 1 goldfish and about 5 others that I can remember the name now.

After substrate is added from bottom of tank to the ligh source it is about 13-14 inches.

My questions:

1.) Do I get a Cool White LED that is 6000k is this Kelvin good?

2.) Should I get one of the lights below from Amazon?

Quantity 1 - 10 watt 6000k -
Quantity 2 - 20 watt 6000k -

3.) Looking to mount both lights under stock hood and so they will be about 2" maybe a little less from top of water surface is that ok? These shouldn't generate a ton of heat right?

I've been reading posts like this that shows what PAR readings are from certain distances from 10w & 20w lights, but it's a lot to take in lol

Please help. I've been doing tons of reading on this site and ready to pull the trigger. I'm afraid if 20 watt is to much light and then I have an imbalance in what the tank ecosystem is producing vs. the amount of light and then having a Algae problem because of to much light causing more harm to the plants etc...Any help would be appreciate.

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I've read that these flood lights quit working 8 months down the road. They say the drivers go out on them. If you decide on them I would have a backup plan for if they fail

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Thanks for the reply. They are cheap so maybe I'll order a 3rd as backup :) lol on that note should I get the 2 - 10 watt or 2 - 20 watt?

I think you should go with the 2 20w. If things seem out of balance run the lights for less time. Continue to reduce or increase the light cycle until you find a balance. You can also use light diffusers or mount the lights using a system that allows you to raise or lower the lights to increase or decrease brightness.

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two 30 watt LED Flood lights at 6000k would be to much light right? Especially since I'm hanging them under the stock hood of the tank.
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