Replacing MH lights with LED Floodlights

[Gribbs01]

I'm planning a 190 cm long, 50 cm wide by 70 cm high planted discus tank - plants will be Amazon swords and anubias nana. Planning on using ADA power substrate and pool filter sand substrate with CO2 injection. I have been given a 6ft marine MH light fitting, it has three 200W MH globes, moonlights and two strips of T5 lighting. I'm thinking of stripping out the MH fittings and replacing with 100W or 50W LED spotlights with a CCT of 6000-6500K. The light fitting will not be seen so will remodel to allow for ventilation. Any feedback is very welcome.

Stu

[Nathan]

If all your going to be growing is swords and anubias the two t5 lights will certainly do the job alone as these are very easy to grow. If that's why I was going to grow I wouldn't bother with ada substrate and just use some fertilizer tablets in the sand.

Keep us updated

[Gribbs01]

Thanks for the advice Nathan. I was also thinking the ADA might be an overkill! Will use fertilizer tabs. I have done some more research on LED spotlights and seem to be a good option for a small outlay. Will keep posting on progress.

[Nathan]

Sounds good, just be aware led spotlights do leave shadows so you will find plants in the shadows of your hard scape won't get as much light. I didn't realize that and some of my smaller plants near driftwood we aren't getting any light an have died

[lshu]

I've got a 5x2x2 which has been up and running for a couple of years now with plants which require similar light. Originally installed 3x50W LED floodies. Get great growth from them but reliability needs to be considered, I think the longest an original unit lasted was around 14 months, these days its an abosolute frankenstein of different drivers and lamps.

I've seen posts claiming the 30W floodies have a far greater life span. I plan to phase the 50W's out as they fail and install 30W's, probably end up with 4. I want to reduce the light intensity as even though the tank is heavily planted with a heap of fast growing stems and C02 pumping, algae on the glass is still an issue after a couple of weeks.

Penetration of the 30W's over 70cm is the only question, but given the low demands of the plants listed, maybe.

[Nathan]

Yeah thats a tricky one about the light penetration depth. Is the lighting unit going to be DIY? in regards to the algae on the glass what sort is it and are you using fertilers?