• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Why is this happening?


13 Dec 2009
Tank specifications - 240l
Lighting - 2x40w T8 - 7 hours
CO2 - Pressurised FE, 4 bps - drop checker showing correct colour yellow/green, on 1 hour before lights, off 1 hour before lights out.
Filtration - ext filter 1000l/h, koralia 1500l/h

Fertilisation routine - 500ml pre mixed bottles
9 teaspoons KNO3 + 5 teaspoons KH2PO4 - Dose 40ml - Mon, Wed, Fri
6 Teaspoons traces - Dose 60ml - Tue Thurs

This is happening to my dwarf hairgrass right across the tank. I pruned it back when i planted it all, and since then theres just the odd shoot growing out of each clump but the majority of it has just not grown at all. Any ideas whats causing this?



It can take a bit to get going so give it time. You're lighting is suite low though so that could be adding to the problem. It probably wont be a major issue, but I would have the CO2 coming on 2hrs before the lights so the levels build up enough, that is of course unless you've got excellent dissolving of the CO2.

Sam when you say his light is quite low do you mean the length of time it's on or something else? As I seem to be having the same issue as above but only after I cut my cuttings and planted then elsewhere.
He means that 80w of light is low level (output) for a 240l tank.
What is the substrate? May help to diagnose the problem but maybe not :lol: looks inert form your pics, anything under it?
More light (either more intensity or photoperiod or both) and you need to split the clumps of hairgrass more.

Looks like your CO2, nutrients and circulation are good, so light and planting technique are your weakest links. Substrate shouldn't matter so much. Hairgrass isn't fussy.
I have cut back Eleocharis sp back to the substrate after initial planting the same as you. Give it a little time, and it will kick off. Then there will be no stopping it. You may experience a little algae around the stubble left behind.

As an aside, when I add it to a tank with uber high CO2, I never need to cut it back, as it seems to make the transition from immersed to emersed with no problems when the CO2 is good. This applies to just about every plant I have added in this way from my propagator.

i will spend some time splitting the clumps up more, and have adjusted the co2 to come on 2 hrs before lights on. thanks for the advice!