Single 36" T5HO

[Shangrila]

I have a 2 x 39w T5HO (36") light above my tank. I seems a little dim at the substrate level as the tank is 21" deep. I would like to add one additional single 36" HO fixture along side my exsisting one. Does anyone know where I can find such a light? I could just purchase another double fixture like I have, but I don't want to end up with too much light.

[Seattle_Aquarist]

Originally Posted by Shangrila

I have a 2 x 39w T5HO (36") light above my tank. I seems a little dim at the substrate level as the tank is 21" deep. I would like to add one additional single 36" HO fixture along side my exsisting one. Does anyone know where I can find such a light? I could just purchase another double fixture like I have, but I don't want to end up with too much light.

Hi Shangrila,

First a few of quick questions, is you light suspended above the tank or level with the top rim? What spectrum (K) are the bulbs? When was the last time the bulbs were changed?

In theory, two T5HO bulbs with good reflectors over a 21" tall tank should be medium/high light.

[Shangrila]

The light fixture and bulbs are brand new. 6500k temp sitting about 1 inch above the tank rim. I forgot yo mention that the tank is 18" back to front. With the light sitting mor towards the back half of the tank. The dim area is more toward the front. If I move the light to the middle the front and back become dim.

[Seattle_Aquarist]

Originally Posted by Shangrila

The light fixture and bulbs are brand new. 6500k temp sitting about 1 inch above the tank rim. I forgot yo mention that the tank is 18" back to front. With the light sitting mor towards the back half of the tank. The dim area is more toward the front. If I move the light to the middle the front and back become dim.

Hi Shangrila,

You might try raising the fixture another inch or so and see if that helps the overall effect. With the light you have I hope you have CO2, if you decide to add an additional bulb/fixture CO2 will be a necessity.

-Roy