How Much Light?

[discus dreamer]

Hi
I am having trouble sorting out the right lighting requirements for my larger tank.
The tank is 38" x 15" and 18" deep(i.e., top to bottom) and I want to have good plant growth. Some things are doing ok but the Glossostigma elatinoides I got for a low carpet at the front has pretty much died off. The lights I have at the moment are 1x30w tripower and 1x30w superlight both the full length (or nearly) of the tank. They are on for two periods of 5 hours with a 2 hour break in the middle. Were on for 12 hours but in total but I have a bit of trouble with beard algae so reduced it.
The plants are in a sand then gravel substrate, have CO2 added and a weekly dose of Plantamin but I must admit nothing like what it says on the bottle (5ml for 20 L every 4 weeks) I have been doing more like only 20ml for the whole 200 L once a week along with the water change.
I have looked at the pinned topics and other stuff on the web re. lighting but for someone starting out who struggles with basic maths its pretty hard to work out what I need for this specific tank.
thanks
DD

 

[DaveW]

Hi DD,
You have a 56 US gallon tank with 60 watts of light which equals 1 watt per gallon.
From Georges experience you can grow Glossostigma elatinoides in 2.2 WPG. If you add another 2 tubes of 30 watts it will give you just over 2.1 WPG.
But you will have to make sure your CO2 levels are up around 25 to 30 ppm, have you got a DIY or pressurised CO2? And also, you will probably need to start to follow the EI method of fertilising.
The three go together - light, CO2 & fertilising. If you don't have all three then you will end up with an aglae.
It takes a little bit to understand I KNOW, but it's worth it. I had to read the pinned topics a few times myself.

 

[discus dreamer]

Thanks Dave W
is it possible to increase the light by having more powerful tubes as i don't know with my hood set up (it's an Aqua One Regency) how it would be possible to add more tubes?
DD

 

[DaveW]

Thanks Dave W
is it possible to increase the light by having more powerful tubes as i don't know with my hood set up (it's an Aqua One Regency) how it would be possible to add more tubes?
DD

You can't simply replace your tubes with more powerful ones. You will need to find a way of adding extra tubes. If you do a search for lighting upgrade you should be able to find something that might help you.

I've need seen a Aqua One hood before, but looking at Aqua One's web site, the lighting comes in a unit. If there is more for another unit in your hood, then email they to see if you can buy a second lighting unit. That would probably be the easiest way to go .

 

[discus dreamer]

Thanks
I'll see what they suggest
DD