What kind of algae: Hair, thread..beard? & what do I do?

[nursie]

I have an outbreak of algae. It started as a few curley threads...pulled off easily. They became more numerous..and spread. I cut off ends of val...and it's exploded..sort of. A lot of my val and corkscrew val have it on th upper few inches. I'd read to twirl it off with a toothbrush..no can do. Tried scraping off with fingernails...if I can without breaking leaves...seems to leave a residue. I don't have any on gravel, sides of tank...anything else. It seems to be kind of a blue green tinged.
I have a 55 gal tank which I'm dosing as follows:
15 ml Excel every other day
5 ml of Flourish 2 x per wk
5 ml Flourish Iron 2 x per week
4-5 drops Fleet enema 2 x per week
15 ml of potassium made from solution of 1 TBSP/300 ml water solution
3/4 tsp Green lite stump dissolver...dissolved in water.

I have a 2 bulb regular output fluorecent bulb light strip: I estimate 1.5 wpg.
I do not use Co2.

For plants I have:
corkscrew val
regular val
red wendti crypt
african fern
3-4 different strains of Java fern on 3 smallish pieces of driftwood.
duckweed..purely voluntary.

as a note..I did have hornwort...and decided to get rid if it because it kept growing so fast and obstructed light to the lower levels of the tank. Soon after I got rid of it, is when I noticed the first of this algae, and also some green spot algae. I scraped the green spot off, but missed a couple of spots on the front glass of the tank...it's stayed the same, not grown. Also around this time I had been dosing the Excel 7.5 ml daily, and made the change to 15 ml every other day.

Filtration is a Filstar XP2, with foam, polyester fiberfil, and biostars.
I do 50% water changes weekly.
I probably tend to over feed.

I've had this tank going since the beginning of March..I hate to dig it all up
I just got everything rooted well.

Suggestions? I can post pics if needed.

[Quartermain]

I'm hardly an expert but I'll bet that when you removed the hornwort you removed a significant ability of the tank to filter nutrients from the water. In any biological filter the bacterial culture will grow only as large as it needs to to consume excess ammonium. But the plants are consuming ammonium too and that hornwort was probably consuming a lot of it. Remove the hornwort and you then have an excess of ammonium until your bio culture expands to consume the excess. Algae will grow faster so it gets there first. It's all a matter of who gets their first. This is just an educated guess of course. But the first thing I'd try is to go out an buy a bag of Bio-Spira, dump that in there, and see if the algae doesn't start dissapearing. Cutting back on ferts for the meanwhile wouldn't be a bad idea either. Starve as much of the algae as you can. Get the nitrifying bacteria to take over. From what I understand algae has a harder time metabolising nitrates, assuming they can do it at all.

[nursie]

I haven't added any ferts yesterday or today, just the Excel. Is this something I should use the blackout treatment for?

[Quartermain]

I've never tried a blackout myself, so I don't know if it will work. Other people seem to have had success with that method. My gut feeling is that it will work (after all the algae need sunlight just as much as plants do) but I'm guessing the algae won't whither away over night. The blackout may have to last quite a while.

My diagnosis is assuming the cause of the aglae bloom is excess ammonium. It only takes a little. My suggestion to use bio-spira was off-the-cuff. I've never tried that either. Other than chemical warfare (ie. bleach) the only method that's been successful for me is the starvation method.

My 10 gal was once infested with diatom and green spot algae. I began perfroming 50% water changes twice a week for about two and a half weeks. I did not dose ferts during this time. I only adjusted the pH of my tap water becuase it is very high. After just over two weeks my tank was cmopletely clear of visible algae. Even the leaves on my Anubias were clean. The advantage to the 10gal may be that it's a very small environment and things don't take quite as long to change, but it is a guaranteed method. Algae don't live long without food. Your plants have stores of energy and will be fine durring this period.

[Left C]

I'd lay off of the ferts for a while to see what happens. Then I'd do the 'blackout' if needed. Hornwort also has a compound that it secreats to inhibit algae growth. Add the hornwort back for a while???