Hairgrass Algae ID

[jimmy james]

Hi,
I have a 18'x10'x10 open top tank iwagumi style with eleocharis acicularis, hemianthus callitrichoides, and some blyxa japonia, 18 ember tetras, approx 30 litres, the filter is an external eheim ecco 130 turning over 500lph, lighting is TMC aqua beam 500 duo reef white 8 hour period, pressurised co2 2bps 25ppm, temp 24 degrees c, ph 6.9, dose 1ml tropica nutrition plus daily, 50% water change weekly. The system has been running for 4 months and everything has been growing well. A thin film has appeared on the surface recently so I moved the outlet pipe up to create more surface agitation to break it up. Can someone tell me what algae this is and how to eradicate it. Hope fully photo attached.
Thanks.

 

[mlgt]

How long is the hairgrass? I know to encourage beter growth Ive been told to trim it down to about 1 cm.
However If you had a bigger picture of the tank? Possibly you need more flow to the hairgrass?

To me it looks like its just run out of legroom.

 

[jimmy james]

I have trimmed the majority of the algae off. It was about 5 inches towards the back graduating down to about 1 inch at the front. The hairgrass covers about 50% of the substrate in between the rocks, 20% rock, 20% hemianthus cuba and 10% bare. The water does flow over the grass. Should I up nutrients, cut down on light, increase co2? Black out? Also on one of the rocks it looks like there is a small amount of what looks like cyno bacteria? Thanks.

 

[George Farmer]

Give everything a good prune. Clean all algae off rocks etc.

Do 2x 75% water changes one after the other right after the pruning and cleaning.

Clean your filter.

Try dosing 3ml TPN+ per day and up the CO2 slightly. Is the CO2 getting all over the tank?

Carry out 3x 50% water changes per week. Should only take minutes in a small tank like that.

Good luck!

 

[jimmy james]

Thanks for that. I did clean out the filter last night, it did blow aload of rubbish back in when i restarted it but then cleared up after a while ,so i'll carry out the water changes accordingly. The plants at each end of the tank have co2 bubbles over them but i'll increase the rate. Should i take out the rock and brush it with easy carbo or will that disturb the substrate and potentially lead to more problems? Or brush it in situ at the 75% water change? Thanks.

 

[flygja]

Honestly speaking, I can't see the algae at all. Is it some sorta green hair type algae? If it is you need to trim and throw as much as possible away.