Lighting power and plants?

[ricey0809]

Hey guys, i was just woundering if i ever wanted to start a planted tank what are the light power rules for each gal.( im using a 10 gal tank at the time.
I have heard some where that it was 2 watts per gallon, but if your tank is
10 gal or less 15 watts would do since anything less then 10 gal would be so much smaller.

Im actually thinking of making a glosso carpet after i get my tank cycled, but im kinda concerned that my life-go 6700k 15watt light wouldnt be enuff.

Also i wanna ask if Co2 injections would do any harm such as lower/rise the PH level or maybe make the oxygen level unsafe for fishes.

 

[Danyal]

the watt per gallon is about as useless as the inch per gallon, there is a huge difference beteen a 2w bulb over a 1g tank and a 40w bulb over a 20g tank. if you want to keep some of the more light loving plants like glosso it would be a good idea to upgrade your lighting to a 36w power compact system. co2 injection can lower ph if you put in too much, it won't affect the oxygen levels however.

 

[ricey0809]

awww and i jsut brought this life-go 15 watt bub for like 20ish$

 

[Danyal]

you can still use it for a number of low light plants, java moss(mosses in general really, java is just very cheap and easy to get) java fern, wisteria, anubias, moss balls etc. you could also probably add on another 15w strip light and have enough light for some of the high-light plants.

 

[ricey0809]

well i actually jsut brought a new cover (one strill insert) and a new life-go 6700k for a decent amount of money. lol i have used so much money already for this tank, and i really dont wanna waste anymore money. i mean would glosso plant really notice that i have a 15watt instead of a 30ish watt? hehe the light seems pretty strong and bright for my small tank

lol as you can see im really new at this whole fish keeping thing and have so much questions

 

[Danyal]

lol as you can see im really new at this whole fish keeping thing and have so much questions

eh, we were all in your shoes once. i learned a lot from doing exactly what you're doing, asking questions on a friendly forum(although i was on wetwebfotos) only i spent 8 years learning the hard way how not to keep fish before i started to learn about them.

i mean would glosso plant really notice that i have a 15watt instead of a 30ish watt? hehe the light seems pretty strong and bright for my small tank

your eyes probably won't see too much of a difference between 15 and 30 watts, but that is because our eyes don't see the exact same spectrum light that the plants use. the choloroplasts in the plant cells absorb light mainly in the red and blue spectrums and reflect green spectrum light(hence why they look green) so the more red and blue light you have in the tank the more light for your plants, our eyes don't see blue and red as well as more of the middle colours(for our purpose just refered to as white light because blended together they appear white to us) so the more light the bulb puts out that is between red and blue spectrum the brighter the light appears to our eyes but the less useful it is for plants.
watts is also not a very good judgment of how much light a bulb puts out, incandesent and halogen bulbs might use 100w but 75w of that energy is emited as useless heat, while some bulbs of the same wattage will put different amounts of light into the tank based on their shape(pc vs t5HO, the pc is just a bent t5 but puts less light into the tank) bulbs of the same wattage can also put out different spectrums, for example a 15 watt actinic would put out almost pure blue light and wouldn't be very suitable for plants while a 15w full spectrum would have enough red and blue spectrum to sustain some plants. visible light output can be measured in lumens, the higher lumens the more light. over driving a bulb a normal output bulb(ODNO for short, basically making it use more electricity) will increase the amount of lumens it produces but not very effeciently, basically a 2x ODNO bulb(example: pumping 30w into your 15w bulb) will make it produce more lumens but not as much as having 2x15w bulbs. then there is PAR which, irrc, is a measure of how much usuable light(for photosynthetic organisms) is produced and that can vary indepentant of watts used, a 20w compact floresent bulb of the right spectrum will produce much more PAR then a 100w incandesent bulb.

 

[ricey0809]

wow ty so much for explaining that to me. now i understand more, haha i never knew having a fish tank was so much work. back then i just thought throw some water in and throw some fish in and there you have it. *back those days were so much more simple* haha

 

[WyldFya]

the watt per gallon is about as useless as the inch per gallon, there is a huge difference beteen a 2w bulb over a 1g tank and a 40w bulb over a 20g tank. if you want to keep some of the more light loving plants like glosso it would be a good idea to upgrade your lighting to a 36w power compact system. co2 injection can lower ph if you put in too much, it won't affect the oxygen levels however.

Actually, CO2 affects you pH always. The more CO2 you have, the lower your pH will go. CO2 does directly affect your O2 levels as well. CO2 and O2 are both dissolved into the water, which can only hold so much. Take into consideration your different nutrient levels which are also in that space. Then there is the part where the CO2 is converted into O2 by the plants. So depending on how good your setup is, and how many plants you have, co2 can actually raise your O2 levels.

 

[WyldFya]

well i actually jsut brought a new cover (one strill insert) and a new life-go 6700k for a decent amount of money. lol i have used so much money already for this tank, and i really dont wanna waste anymore money. i mean would glosso plant really notice that i have a 15watt instead of a 30ish watt? hehe the light seems pretty strong and bright for my small tank

lol as you can see im really new at this whole fish keeping thing and have so much questions

In a 10 gallon tank with 15W of T8 lighting, you won't get much growth, and likely die off. Glosso also needs to have CO2 in order to grow well. It is a very high light plant as well, and needs good strong lighting.

 

[WyldFya]

Hey guys, i was just woundering if i ever wanted to start a planted tank what are the light power rules for each gal.( im using a 10 gal tank at the time.
I have heard some where that it was 2 watts per gallon, but if your tank is
10 gal or less 15 watts would do since anything less then 10 gal would be so much smaller.

Im actually thinking of making a glosso carpet after i get my tank cycled, but im kinda concerned that my life-go 6700k 15watt light wouldnt be enuff.

Also i wanna ask if Co2 injections would do any harm such as lower/rise the PH level or maybe make the oxygen level unsafe for fishes.

Read the stickies about The end of WPG. That will explain in depth much more for you.