When ?

[sdlra]

there is always a lot of debate about when to turn on and off co2 is there a right or wrong answer ? At present mine goes on at the same time as my lights but goes off an hr before my lights go off is this ok ?

 

[bigmatt]

Conventional wisdom is to have the gas come on 2 hours before the lights so that you have maximum co2 concentration when the lights come on. However, if you're getting good growth and no CO2 related algae don't touch anything!!!!!
Hope this helps
Matt

 

[sdlra]

no just getting a very light film on top of the tank just wondering if i need more co2 at the start. have good water movement 50% water changes just this slight film puzzling me

 

[Garuf]

An hour is generally what's recommended, this means that you're not inadvertently underdosing without realising, it however depends entirely on the tank and your set up.

Generally speaking you should always have the co2 on before the lights to allow the water to saturate to the required levels before the lights kick in triggering co2 demand.

 

[sdlra]

just concerened the slight film on top is due to lack of co2 despite good indicator etc...... good water movement 50% water chacges good filtration just that bit need to master

 

[Radik]

I turn co2 at 4 hours before lights on and turn off 5 hours before lights off. So 6:00 AM Co2 on, 10:00 lights on, 12:00 co2 off, 17:00 lights off. You should aim to have good co2 when ligths turn on. There was topic from Clive explaining why. About your film there is also topic just search throgh forum what is the cause.

 

[Bobtastic]

I have mine set to come on an hour b4 the lights and goes off an hour b4 the lights too. I would be interested to know the cause of the surface film as well. I noticed my tank had a film last night, the only thing I can put this down to is that the curtains were left open all day and the amount of light that it would normally receive would have been increased.

 

[sdlra]

I have increased the surface movement at the top and this seems to have done the trick