Please help me figure out my lighting, ferts and CO2!

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I have a lot of trouble figuring out how much light and CO2 I have, and what plants would thrive in my tank. I could also use some help dosing ferts.

My tank is about 120gallon or 540liters. I have 2 18w LEDs, (AquaEl) one at 10 000k and one at 6500k. I can't figure out what their PUR/PAR or Lux is, which I don't know much about in the first place. They're only 1m long, while my tank is 1.5m long, so they overlap at the middle. I also have 2 T5 80w that I'll hopefully be able to install (fixture broke).

I also have this weird CO2 set. I can apparently choose how much CO2 it releases. In addition I have purchased an allround water column fertilizer and root tabs. I have a sand substrate with 0.2-1mm coarseness. And a little bit of floredepot to put beneath it.

Right now I'm in the planning process of reworking my tank. I want it to be heavily planted, and I'm fine with low-tech plants. I'm sorry for this massive infodump, and I really hope I can get some advice! What kind of plants can I grow in this tank? I'm adding a picture of the general aquascape feel I'm going for with my tank.


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Most plants do well with a tropical temperature and a lot do well with that pH, so you will have some nice choices. :) What fish are you planning on getting? Larger fish will eat some kinds of plants. For a planted tank I would recommend some otocinclus, plecos, maybe shrimp if you are careful with c02, and a school of smaller fish such as danios or rasboras.
Here's some plants you might want to try that will do well with the pH and temperature:

  • Red ludwigia
  • African onion plant
  • Banana plant
  • Madagascar lace plant (I love this plant and have a little farm going; you will need a good filter to prevent particles from becoming stuck in the leaves)
  • Java fern
  • Lacy (windolev) java fern
There are many more, and here is a link to so you can look for yourself.
Thanks a lot. As this is a rework of my existing tank i already keep a lot of fish, including catfishes, plecos and clown loaches. I'll look into those plants! With the lighting I got, how much CO2 should I dose and how much ferts if the tank is heavily planted?
Firstly i would only recommend the dosing that it states on the bottle of the fertiliser that you have purchased, If you want to go more in depth you can do some research on what plants need and then what that bottle has and then maybe fill in what you are missing to get more.. However if you are low lighting but high tech tank you wont need to much extras. If anything with the low light levels you may find you can dose at 50% your plants will tell you if they are missing any nutrients by there colour/shape what part or how they die off.

With the Co2 you can work this out very easily by using a Bromel Blue Drop checker in the tank a good guide is here.

Highly recommend getting one of those so you know exactly how much Co2 is in the tank. long story short light green is what you are after :)

with your size tank i would add some amazon swords they are very large plants and i love LOVE the look of them heavy root feeders so the root tabs will be ideal for them.

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