[kendall.j.boykin]

Looking for a reason why my Walstad tank is having this problem. The tank consistently tests 0 across the board but this stuff is still growing. I’m going by Diana Walstads suggestion of a 5-4-5 siesta lighting schedule. The tank does receive some daylight for a couple early morning hours during the time the artificial light is on. I’ve been doing 10% water changes daily with RO water to reduce the amounts minerals in the water from the tap water but still no dent in it.

 

[mysiak]

Yesterday I noticed that I have this algae as well, mainly in the place with strong light (I've added second lamp couple of weeks ago). Tank was pretty much algae free for few months and my water parameter readings and light schedule is same as yours. I am experimenting with light intensity now - I've moved both lamps a bit further away from the tank to see what happens. My suspicion for algae growth is combination of lack of macros (mainly Nitrogen), abundance of micro nutrients from soil (Iron?) and too strong light.

Could you please share some photos and description of your tank? Mine is here http://www.aquaticplantcentral.com/forumapc/el-natural/138594-10l-2-5g-bowl-13.html