What is going on with live plants.

[lilacamy931]

I've had my tank set up for 5 months now and built up and replaced various aquatic plants.

I'm going through various algae and plants dying off stage and could do with some good advice what I can do to get a healthier tank?

200 litre, fine sand bottom, fluval aquasky on 8 hours per day timer.
Weekly water change of 40%
Daily dosing CO2 (occasionally forget) and weekly dosing ferts.

Mopani, bogwood and moss balls in tank.
Plants doing okayish are anubias, crypts, foreground plants.

Plants suffering are background plants which include swords. These plants have gone lighter green, some transulent and some dying away.

The anubia has mottling on leaves and currently black furrish algae edge of leaves.

Is there anything I can do differently and I want to make more dense again - better options to go for?

Attached thumbnails of tank

 

[Hendre]

Do you give your swords any root feeding? It could most likely be a fertiliser deficiency that leads to issues. On anubias try a hydrogen peroxide or Seachem excel spray, lot's of details on how to do it scattered on the interwebs. Slow growing plants such as anubias are prone to getting algal growth

 

[Deadliestviper7]

You need snails and other algae eating critters,makes it a lot easier.

 

[fisheatfish]

Green spot algae and black beard algae can be resolved with hydrogen peroxide. I spot treat with a dropper on occasion. Better method would be to do a big water change and spray everything with H2O2 then refill aquarium.

Prevention would be a better method. Appears you have plenty of plants to absorb the nutrients. Intense lighting for too long may be your issue.

Appears your substrate is a bit low...swords are big time root feeders.

 

[Fat Homer]

You are most likely getting GSA (green spot algae) because of a lack in phosphates in the tank...

The black beard algae is caused most likely because of the fluctuating Co2 levels...

 

[Fat Homer]

Forgot to add, you still need to be careful dosing peroxide as well, since some plants are senstive to it along with shrimp if they come in direct contact with it when dosing...

So better to fix the route cause than add a bandaid to the tank coz it will keep coming back...

 

[lilacamy931]

Thanks so much for the replies.

Gained some root tabs and planted these in the substrate near roots of the plants.

Unfortunately snails are a no go due to puffers. However there are amano, cherry shrimp and bristlenoses in there.

I will adjust light parameters etc and try to remember regular CO2 dosing.