[Aqua5-0]

Hi all, my tank will be using strictly rain water (this is all I have access to)... I can only guess that there will be many "nutrients" missing?

Right now I only have Flourish and Flourish Iron... What else do I need (if any) regarding fertilizers?

Should I be dosing higher than recommended? due to the lack of nutrients?

What should my dosing schedule be like?

I haven't set-up my tank yet so I cannot tell you how the plants are growing. And as far as my water goes, I've only tested the PH which was about 6 or 6.5. Hardness?


Thanks for your expertise

Josh

55gal, 260W CF, CO2, Eco-Complete

 

[HeyPK]

I use rainwater by choice, because my tap water is high in sodium bicarbonate and has none of the macronutrients, N, P, K, Ca, Mg, or S. The most immediate thing rainwater needs is some lime, ground limestone or oyster shells to get Ca and Mg levels up. I want the calcium content to get up to the 50 to 100 ppm level. I then add KCl or some kind of potassium salt to get the K level up to 20 to 50 ppm. This will last a long time. I also add some magnesium sulfate just to make sure of Mg levels. I add a trace element mixture, and that takes care of everything except N and P.

N and P should be added frequently enough to keep levels measurable with test kits. This can be once a week or once every two weeks. Iron should be added at around the same time. I don't find that nitrate levels have to be maintained higher than 10 ppm as some people are saying, although it doesn't seem to hurt anything to do that if you want to.

I don't worry about Ca, Mg, K. and S and the micronutrients after my initial additions. After one or two major harvests of plants and seveal months, I check K levels, and usually they are still up there. I don't do water changes very frequently, and it has been my experience that the K, Mg, Ca, SO4, and micronutrients last for a very long time.

 

[Raul-7]

To make your life easier just use Seachem's Equilibrium(it restores and maintains mineral balance), it's made specifically for RO/DI and rainwater.