moss like plant growing on compost in plug trayes

[nemo]

hello i have several new plug trays filled with compost and i have seeds sown the seedlings germinated but the surface of the compost has a green moss like plant growing on it .the tunnel is well ventilated i tried keeping the compost on the dry side in an attempt to stop the moss growing with no sucess they have good light
should i use perlight or somthing similar
what should i do
nemo

[Nature's Babe]

I am wondering if perhaps the drainage holes underneath are a bit small, or perhaps large woody particles in the compost might be blocking the outlets.

[nemo]

thanks nature babe your reploy is after getting me looking atb my problem from a diffrent angle. the plug trays are in aluminum baking sheets i put water in the trays and the plants take up the water i do this when the compost looks dry could this be my problem should i water from overhead and put the plug trays on a shelf so excess water drains from the plugs.its my first year using plug trays i have used a compost blocking machine for years

[Fair Weather 33]

Afternoon nemo

I have had this problem in the past. But it never seemed to affect the seedlings and it went away once I potted them on.

Since then I have used Vermiculite on the top. What I do is put compost in the trays water it well (to let it settle) put more compost in the ones that have sunk too far and water again. Then I let it drain for about half an hour. Put the seed on top of this and fill it up with vermiculit to the depth the seed is supposed to be at. Then I water only from the bottom.

This has worked well for me. It will be interesting to see what the more experienced peeps think.

[Geoff]

Spot on. I'm a great believer in watering before sowing and letting the trays settle to the temperature where you are going to sow before you sow. I cover fine seed with vermiculite but larger seeds like Brassicas with a mixture of vermiculite and fine compost. If they need watering before germination I spray overhead.