Failing Plants

[elmo666]

Hi, I could do with some advice regarding my lightly planted tank that is meant to be heavily planted?? A few details: 100g tank that is moderately stocked with mixed community fish, 48" x 20" wide x 26" deep not including the built in rear trickle filter. Also has an external aqua one 2450 and a low level 1000 lph pump returning from trickle filter. All flow is diffused using rockwork to ensure only a moderate flow through the tank. Substrate is 1.5" of medium/coarse sand. Lighting is 4 x 39w T5 tubes, 2 x lifeglo, 1 x sunglo and a new plant tube. A home made co2 generator is working well producing 1 to 2 bubbles per second, this is tapped into the uptake for the external in an attempt to increase contact time. My lights on on for 11 hours per day, I leave the co2 on all the time. My plants are around 10 bunches of cabomba, 6 elodea densa, 12 straight vallis, 4 hygrophlia and a few others that am not sure about. I have attached java fern to all my bog wood but it isn't spreading. The cabomba originaly did well, reaching the top of the water with lush green tips that opened and closed. Now it just breaks off all the time half way up and is very dark in colour. The hygrophila grows at low level very well, bright green fresh leaves but attains no height, the vallis has shoots but again no height. Black spots are appearing on the leaves of the other low level plants. I have no algael growth worth mentioning, but have read the black spots could be algae, I have also read that the co2 should not run at night? I am aware not using ferts at the moment could be a big issue, and intend to get these when funds allow. My thinking was to try without them initially to avoid any ongoing cost and suspect this may be the "root" cause, if you pardon the pun. Any thoughts would be greatly appreciated. Thanks

 

[SO19Firearms]

Too much light + CO[sub]2[/sub] - Ferts = Sick plants.

Add ferts or drop the lighting down.

IMO

 

[elmo666]

Too much light + CO[sub]2[/sub] - Ferts = Sick plants.

Add ferts or drop the lighting down.

IMO

Too much light + CO[sub]2[/sub] - Ferts = Sick plants.

Add ferts or drop the lighting down.

IMO

Thanks. Would 8 hrs lighting be ok? As you have not mentioned the co2 I am assuming I don't need to vent it off at night. Your imput much appreciated

 

[SO19Firearms]

It depends on what Nitrate and Phosphate you're gaining naturally through Food and waste - I'd guess even 8 hrs is too much.
Get the ferts

 

[elmo666]

Thanks, will do, and will drop the lighting down to 6hrs