Dry start method tank - yellowing leaves

[MedicMan]

Hi all, I started a DSM tank a few months ago and after some trial and error, seem to have got the mix right - mostly.

I'm using amazonia soils with root tabs and a carpet of HC. The HC is spreading now and throwing off lots of runners, but I have noticed some older leaves are starting to look yellow.

The tank has 2*t5 and 1*led panel set at 40-50%. Temperature is kept around 20-24c and a clingfilm wrap is almost 24/7 with about 30 mins off while I mist the tank (weak ro:fert mixture, 2-3x a day). The substrate is very well saturated and no mold as yet.

I'm hoping this isn't something I can't fix! I'm wondering if this is either a deficiency or if it is fertiliser burn from the weak ro:fert mix (0.5ml aquavitro synthesis to 1.5l ro water)

The tank has been flooded and drained a few times to reduce some of the ammonia that was previously burning the leaves.

Any advice?
Pictures as follows

 

[MedicMan]

Sorry about poor picture quality!

 

[MedicMan]

Anyone?

 

[Martin in Holland]

The root tabs might be overdoing it and plants simply "burn"...remember, nutrients are in fact salts and they get moist out of your plant if there is to much of it...(osmosis)

 

[foxfish]

You don't need to spray anything, just keep it sealed.
You can give it loads of light!
I have found by far the best results come from keeping the tank slightly warmer than the sounding air as this causes condensation & high humidity.
I use natural sun light if possible to get fast growth.

 

[MedicMan]

Hi Martin and fox,

Thanks so much for your responses. I'll cut the ferts and see how it goes.

The only reason I was adding ferts was because it seemed to help the fissidens along. Also, since I have flooded and drained the tank a few times, I was concerned there might not be any nutrients left in the soil.

Do you think cutting ferts in the mix would still be OK?

Once again, many thanks!

Please excuse grammar and spelling mistakes in this post. I'm posting from my phone/tablet.

 

[Martin in Holland]

Don't worry about washing out nutrients, it won't happen that easy. The most important nutrient now is CO2.

 

[MedicMan]

Thanks for this Martin, I've turned it over to a pure RO mist and it seems to be getting no better or worse. I imagine it will be a few days more until I see a change


Please excuse grammar and spelling mistakes in this post. I'm posting from my phone/tablet.