so I posted yesterday about wanting to setup a planted tank. I got a few responses which they were all helpful. the biggest thing I am confused on though is lighting. I have heard of wpg and now I have been seeing a new formula. I do not understand it at all. right now I have two t8 lights both 15 watt and my tank is 37 gal. I know I need more lighting but not sure how much more. im not looking for a high light just moderate light. thank you
how much light do i need
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Really depends on the plants you have/want. Anywhere between 2 and 5 wpg. Swords and anubias need a minimum of 2 (and not much more), which in that tank your looking at about 75 watts :O If you are planning on having more light demanding plants, that would obviously go up quickly.
right how I have swords and Anubias. I just ordered hornwort, wisteria, and Hygrophila. I also want some java fern and moss. maybe later would like to add a carpet of some kind.
Growing live plants in an aquarium is a balancing act between light, plants and nutrients. Start slow...the anubias and others you ordered will do ok in the 2wpg suggested by sf. The typical amazon sword, echinodorus amazonicus, can outgrow your tank. I've had them fill half of a 125 gal.
Mark
Mark
I would recommend for tanks under 75 gallons are fluorescent bulbs, either compact or regular and I think you could try this out for your planted tank.
With the setup as-is, ~30watts worth of T8 on a 37g, floating wisteria and/or water sprite and some java fern and anubias on the bottom would probably work with little fuss. A 37 is a super tall 20L.
There are two things roughly covered by this watts per gallon measure, and those are Area to be lit and distance from light. Area to be lit is fairly simple, more area to be lit would need more light, thus a 20 long needs more light than a 10 gallon to have equal lighting.
One consideration for fluorescent lighting is available tube lengths. The 30" length tanks (like your 37) are awkward because they are inbetween two lengths of tube, one to short and the other to long for exact coverage of the length.
So that leaves distance from fixture to bottom of the tank. Light intensity drops off exponentially with distance (Intensity is roughly= 1/distance squared). So to have enough light at the substrate for carpeting plants in your tank would by necesity require high light because of the depth of the tank.
To give an example I had the amout of light you currently have on a regular 20 gallon. My tank is 6 inches less in length and 4 inches less water depth to light. I considered it very low light and experience proved I could only grow easy plants. No carpeting plants would grow in my tank. I also had that same amount of light on a 10 gallon tank and could begin to grow some bottom plants. To light your tank like my 10 gallon and be able to grow easy carpeting plants you would to at least triple the light you have and then it would be a struggle to get them to grow.
I hope this helps you understand your options and the previous posters suggestions, which I agree with.
One consideration for fluorescent lighting is available tube lengths. The 30" length tanks (like your 37) are awkward because they are inbetween two lengths of tube, one to short and the other to long for exact coverage of the length.
So that leaves distance from fixture to bottom of the tank. Light intensity drops off exponentially with distance (Intensity is roughly= 1/distance squared). So to have enough light at the substrate for carpeting plants in your tank would by necesity require high light because of the depth of the tank.
To give an example I had the amout of light you currently have on a regular 20 gallon. My tank is 6 inches less in length and 4 inches less water depth to light. I considered it very low light and experience proved I could only grow easy plants. No carpeting plants would grow in my tank. I also had that same amount of light on a 10 gallon tank and could begin to grow some bottom plants. To light your tank like my 10 gallon and be able to grow easy carpeting plants you would to at least triple the light you have and then it would be a struggle to get them to grow.
I hope this helps you understand your options and the previous posters suggestions, which I agree with.
Hi All
I am using LED -Fluval-Plant- One should be sufficient for most plants. I am using 2 but only one for 6 hrs and another for 4 hrs.
I updated my Tank, moving around some plants and adding some.
At present I am treating the tank for some bacteria/algae and its almost clear, in another day I will power on my UV and add all the Carbon and filtering and the tank should look more clean.
I am using LED -Fluval-Plant- One should be sufficient for most plants. I am using 2 but only one for 6 hrs and another for 4 hrs.
I updated my Tank, moving around some plants and adding some.
At present I am treating the tank for some bacteria/algae and its almost clear, in another day I will power on my UV and add all the Carbon and filtering and the tank should look more clean.
