overflow, sump, hardwater --- deadly combo?

[toffee]

My tank has an overflow, sump, and liquid concrete from tap. No CO2 but 2w/g. Is this a recipe for failure?

trying to grow amazon swords.

[mooner]

The tank, overflow and sump are fine. What is the exact GH of your water and what type of lighting are you using?

[toffee]

gh=300ppm

Tank 6' x 2' x 2'

Lighting:

2 x 140w 60" VHO that covers the back half of the tank (1' x 6'); one of the VHO is 10000k, the other 50/50. I figure the useful lights would be something like 140w + 70w = 210w or so. Since they are covering only the back half of the tank, or about 90g, it translate to about 2w/g??

[epicfish]

Do you only want plants in the back then?

I'd use one bulb at most. You can do burst lighting with the other bulb and have it come on for 3-4 hours during your main photoperiod, but otherwise, both running at the same time may be too much if the bulbs are solely directed at the back half of the tank.

[toffee]

Yes epicfish, I only have plants in the back, may in time to come add some java fern or so towards the front.

As for dividing the 2 lights, that may be hard to do. as the VHO were wired together. I tried to use only one tube but it wouldn't start that way, once the second tubes was added, it started right up.

[epicfish]

Originally Posted by toffee

Yes epicfish, I only have plants in the back, may in time to come add some java fern or so towards the front.

As for dividing the 2 lights, that may be hard to do. as the VHO were wired together. I tried to use only one tube but it wouldn't start that way, once the second tubes was added, it started right up.

You can try to plant very heavily from the start and see how the tank does. You can also try dosing Excel or glutaraldehyde as a lower-cost alternative to help prevent algae from creeping up in your tank.

[toffee]

Do I need to worry about CO2 situation? I am not dosing and the overflow/sump ought to be unkind to CO2 situation?

[epicfish]

You're not injecting CO2, so it doesn't matter.

[toffee]

do i need to? considering the lighting and water?

[epicfish]

Originally Posted by toffee

do i need to? considering the lighting and water?

Might be a good idea if you have the budget. Personally, if you're aiming for slow growing plants, I'd try to run the tank without CO2 first. If the algae starts creeping up on you and it seems unmanageable, then go for pressurized CO2.