Is a 85Watt Fluoresceht light too much for a 20 gallon planted tank?

[jcsaad]

Plants in tank: Water wisteria, anacharis, Alternanthera reineckii, anubias. Currently the tank has a 15 watt fluorescent bulb which is extremely low ligh and so the plants arent growing at all.
Will the new light show me increased growth or will I have an algae bloom? (i add liquid fertilizer each week but no co2 injection)

 

[CA_BroncoFan]

If I had the power I'd put this in the planted tanks section where you'd probably get a lot more help, but in the mean time check it out and welcome to AA

 

[7Enigma]

Without CO2 injection there is no way you won't have a tank full of algae. You *might* be able to mitigate with Flourish Excel (a carbon suppliment) but it is not compatible with certain plants (anacharis), and is probably not enough for such high light.

 

[jcsaad]

ill definitely check out that section thank u ...how strong should the light be??

 

[7Enigma]

Pretty much anything over 40w is going to likely require CO2. As I said you might get away with a liquid carbon suppliment but most people use them under lower-light conditions.

 

[mfdrookie516]

you might want to consider an actinic bulb or bulbs to replace some of the daylight bulbs to knock the wattage down a bit... what kind of fixture is this?

 

[7Enigma]

you might want to consider an actinic bulb or bulbs to replace some of the daylight bulbs to knock the wattage down a bit... what kind of fixture is this?

Hadn't thought of that. That would be the perfect thing to do if possible. If you could get a 50/50 (actinic/daylight) you'd drop your wattage down to a usabe range without the need for CO2. I'm also a bit interested to hear the type of light because that wattage is not a normal one I'm used to seeing posted. 65w is the norm (talking compact flourescent, CF) so 85w is possibly a non-traditional fixture. If non-traditional OP please post how far off of the water surface the light is hanging (that makes a HUGE difference in actual light that reaches the plants).

 

[jcsaad]

Its a regular compact fluorescent light its not made specifically for tanks..it will hang from the top of the tank since I dont have a lid...whats actinic light? i googled it and it gave me a bunch of results for reef tanks :\

 

[mfdrookie516]

actinic bulbs provide a blue light that plants do not use, which make a very nice color in the tank but cut the wattage of the light by replacing the usable light with unusable light.. if its pc lighting, then you can get a 50/50 bulb that is half daylight (6500-10,000k) and half actinic (420-460nm) basically cutting your usable wattage in half

 

[jcsaad]

Ohh ok! thanks a bunch!