From the numerous symptoms that are observable from the picture, the water is most likely hard, likely very high Ca and very low B.
L. "red" - sides of leaves curl heavily under which is a symptom of -B. -B can be induced with very high Ca concentrations.
Crypts - leaf margins are wavy which is a symptom of -Zn. Same with -B, it can be induced by high Ca concentrations.
The algae colonizing the leaf margins are likely a symptom of -Zn.
I've got EXACTLY the same issue. CO2 dosing looks fine, tank and filter media pretty clean, purigen in filter, dosing all nutrients highly enough dosage, lighting period and intensity ok. My growth rates on my plants all seem good but this stuff is horrible and my (true) SAE doesnt seem to want to eat it either. I'm sick of adding H202 and I really didnt want to go back to using flourish excel again but I've bitten the bullet and have started dosing that as well. Following.
I thought I’d update you all on my progress regarding my algae problem. It is now 95% gone, including bba that had been growing on the rocks and wood.
My initial attempts were brought no success. I think I was overcomplicating matters, trying to overdose with fertiliser using the George Foreman technique. Unfortunately, my water here in London is super hard so the excess fertiliser just went into feeding algae.
I came to this conclusion almost by accident as one week I wasn’t able to fertilise and at the end of the week I noticed the algae had reduced. I applied liquid carbon to the remaining problem areas during a water change and tried not fertilising for another week. I’ve kept this pattern up for a month and the algae is almost all gone.
The experts out there will probably say my plants are not in ideal health, but the tank is free of algae and all the plants are growing well, so for now, I’m happy to be a novice scaper.
Cheers Darrel. Yeah, I agree. The technique sounds good - add when you see a need. I’m also going to slowly phase out plants that like soft water in favour for hard water plants. I’ve occasionally dosed after a water change and there are plenty of root tabs in the substrate, but I’ll keep an eye out for any plant deficiencies.
On the moss, it grows like wild fire and unfortunately keeps propagating itself in the carpet. I spend hours removing stray moss...