Is (4) 48" t5 ho fixtures too much light for 90gal?

[Philly33]

Is (4) 48" t5 ho fixtures too much light for 90gal?
I'm only dosing liquid carbon.

 

[Rokuzachi]

What brand of fixture and what are you intending to grow?

I ran a single T5HO over my 100g (wattage is not important, as it scales with length) and was able to grow crypts, ferns, moss, boblitus, swords, lotus, vals, dwarf sag. Check the Lighting An Aquarium With PAR Instead of Watts thread for more info on how to properly light a tank.

 

[aqua_chem]

4 bulbs or 4 fixtures (8 bulbs)?

 

[Philly33]

Sorry, 4 bulbs. My combo lacks 6,700k in the rear. Currently- 6,700 x colormax x aquaflora

 

[gjustinmatz]

I have 3 T5 6700 bulbs over my 90G dosing with co2 and everything except hair grass grows well. I keep 2 of them on 9 hrs. and the 3rd comes on for 3hrs. In the middle of the day.

 

[Rivercats]

You can get away with running high light and using liquid carbon only BUT you have to use liquid carbon in higher amounts. When you have high light, high bio-load, or a lot of plants, especially fast growing stem plants you have to increase the amount of liquid carbon used. I ran my 220g 100% planted high light (metal halides and T5HO's) for over a year using only liquid carbon BUT I had to use 1ml liquid carbon per 1 gallon of tank water. Even Seachem states more Excel may be needed for high production tanks. You can tell when you tank reaches it's max amount of liquid carbon as the water will cloud up but be clear the next day. It is safe but you have to build up your dosage slowly.

Also in the amounts you need I would suggest buying Metricide 14 Day Solution. A gallon is about $27 shipped. You mix it at a 1:1 ratio with RO or distilled water to get 2 gallons for $27. That makes it very economical to use in larger tanks.

Another thing, what ferts do you use? In tanks with high light and liquid carbon or CO2 you really need to be using dry ferts to provide plants with all the micro and macro nutrients they need.

 

[Philly33]

Can I use the EI dry fert method with only liguid carbon? Slowly going to make the jump to pressurized co2 this winter.

 

[Rivercats]

Can I use the EI dry fert method with only liguid carbon? Slowly going to make the jump to pressurized co2 this winter.

Yes you can but remember the higher the light on the tank the more liquid carbon you need. I'd start with 1ml of liquid carbon to every 5g of water and then in a couple weeks go to 1ml of liquid carbon to every 2g of water.

 

[Philly33]

Thank you