Help Getting Rid Of Cyanobacteria (Round Two)?

[FiddleSticks268]

Hello! 
 
I have a 20G long aquarium with aquaclear (fluval) 50G filter, sand substrate, live plants & terra cotta decorations, 4 neon tetras & 5 julii corydoras
 
I have had cyanobacteria for almost a year now.  I didn't realize what it was, and that it was bad until just this spring!  I used Maracyn (erythromycin) to treat it and it went away, but it came back a few weeks later.  I believe this is because it is in my filter media and in the sand.

So here's my plan of action, please tell me what you think!  I removed all the sand, filter media (charcoal, sponge, & biomax rock things), and terra cotta decorations. (I have one plastic rock decoration that my java fern is attached to growing all over it that I left in.)  I am planning on baking these in the oven at 300 degrees for one hour.  Other options include autoclaving or soaking in vinegar followed by a good good good rinse.  Apparently if you soak things in bleach and let them sit out in the sun for a few days the bleach will disappear?  Autoclaving would be the easiest but I'm scared it might melt everything?? Does anyone have experience with that? 
 
I for sure have to do something with the sand.  I can throw away the decorations and the filter media but I'd rather not have to pay to buy everything again.
 
The other half of my plan is to dose my tank with 400mg erythromycin every 24 hrs for 5 days with the filter running (no media).   So this will hopefully zap the glass walls, plants, fish, and inside of the filter box.   Then do a 50% water change and start cycling the tank from scratch. 

Long term I would like to get back up to 6 neon tetras, 6 corydoras, and 2 african dwarf frogs.  This time I will quarantine so I never have to deal with this again!!!!  (I was only ever allowed to have one fish tank before so quarantining was impossible.)
 
Will this work to get rid of my cyanobacteria???
 
Thanks!!

Oh yeah, and I am thinking of doing a 3 day blackout before I start.

 

[levahe]

Hi there, cyanobacteria is often caused by low nitrates. What ferts do I you feed your plants and do you add co2?

 

[FiddleSticks268]

I do not add CO2--my tank is not fully planted. I have some java fern, a bunch of christmas moss, and some dwarf hairgrass but the tank is still mostly bare bottom.  I have the equipment to do a DIU yeast CO2 injector but I haven't built it yet.  I was thinking I would wait till I have a ton more plants. Here's the fertilizer I use--I don't use it that often, maybe once every 2-3 months?    http/www.petco.com/product/3997/Tetra-Flora-Pride-Iron-Intensive-Fertilizer.aspx?CoreCat=OnSiteSearch  

 

[levahe]

I never had cyanobacteria myself but from what I have read on the 'net its caused by low nitrates and it could be caused by not enough tank maintenance/dirty filter and not enough flow. Do any of those apply?
Do you do decent sized weekly water changes? That could give you enough nitrates.
From what i have read a 3 or 4 day blackout can help also

 

[FiddleSticks268]

So I just started reading the planted tank forums and I also had a ton of green hair algae that just popped up.  Does that mean I am not adding enough nutrients and CO2?  I thought that reducing it would make it harder for the algae to grow but it sounds like that was the opposite of what I needed to do?  I've also heard overfeeding can cause algae growth--how do I know what is too much vs. enough? 

I have a 50 gallon filter for a 20 gallon tank so it should be filtered very well assuming my filter is accurate if going by the 2x the gallonage for filtration.  I could probably rinse out the filter more often but I just got a new filter about 6 weeks ago.  Should I be cleaning it weekly?  Or monthly?  I think I've been averaging 2 months that I rinse it out.  I admit there's a lot I don't know about fishkeeping that I just assume (probably wrongly)     I add 20% water about every 2 weeks as it evaporates out.  I thought water changes reduce nitrates?

 

[levahe]

To maintain a healthy tank, planted or not its essential to carry out water changes. A good starting point would be 25% a week or more if you wish. Just topping up the water is not enough because you need to take out 'dirty' water and replace it with fresh. The fresh water also contains minerals and so on that your plants/fish need. Your fish will appreciate the fresh water too.

As far as I know pretty much all tap water contains nitrates so if you do decent sized changes every week this would cover it. you need to keep your tank and gravel as clean as you can and ensure that there is enough flow getting around your tank.
Over feeding can cause water quality issues and ultimately combined with lack of house keeping and waterchanges will cause algae.

If i was you i would start weekly water changes and a weekly gravel vac, and add ferts weekly. You can safely add more than the recommended dose for ferts.

 

[gtk]

over 2 years. I have had 3 small tanks and I now have RIO240 some think its big others small. One of my biggest mistakes was when Moving my fish to a new tank I cleaned every thing to much. Never put fish in a tank with new media. you will get rid of the green for a while but by cycling the tank with clean media you will kill lots of the fish.
 
I would change the water small and often 20% every morning, cut back or stop food for a week.
take out plastic toys for a scrub with water only (make sure no fish in them only caught out 3 times by the plecs and a loach) quick reflex save the poor fish.
 
I have heard flake as a lot of phosphate and to much feeding can build up in the tank. so I am trying Daphnia and blood worm change is good for the fish I was told.
Swim blader is helped by this to.
 
I have heard UV clarifier lamps can often clear green water.
So I am thinking of getting a filter with one built in.
 
If anything I said is incorrect dont hesitate to let me know. still on the learning curve.