I have a 96 cf quad 6700 (about a year and four months old) and a 40 cf 10,000 and 40 cf actinic (a year old) over a 20 inch cube.

in the last couple of months I've seen a lot of bba and green spot.

before that I had well more snails for the spot algae, and a ton of pearling and no algae at all.. Still dosing EI, water changes weekly, and co2 is full.

can the algae be because the bulbs are old ... maybe changing the light frequency they send out? It was a friend's guess, but I hate to toss out good bulbs unless the guess makes sense.

BBA building up suggests you don't have enough CO2 dissolved in the water. If you make or buy a drop checker, use it with 4dKH distilled water in it, you can be sure you have enough CO2. GSA tends to show you don't have enough phosphates in the water, so increasing the phosphate dosing by about 50% should help that. I don't think there is any chance that aging bulbs are your problem.

I still have a pair of 6 years old PC light bulbs, no issues relating to algae, if anything, you see less, not more algae as the bulbs lose power.

You have a CO2 issue, not a light bulb issue.

Regards,
Tom Barr

great. Upping the co2 and phosphate is the cheapest solution... I'll wait until Saturday so I can monitor the fish as I do that.

Thanks!!! I hate to toss bulbs when replacements are so expensive.

The R macrandra should respond well to increased CO2, good NO3/PO4 and GH.

Place the weed in the path of the CO2 mist, it should do very well there.

Regards,
Tom Barr

Tom you are probably a little brilliant and a litte psychic!. I went to check my co2 and it had emptied!!!!! It had maybe a few bubble left, but must have been running on low pressure for a couple of weeks because when I upped the bubble count, my cannister was empty within 2 hours.

I never thought of that because it had been filled 3 months ago and the last cannister lasted 8 months -- I figured this one for a year because I had taken your advice and had started shutting it down with the lights.

No wonder I've been fighting algae!!! eesh. the only co2 hit those plants were getting was during weekly water changes. I wasn't even using excel.

Canister gets filled first thing Monday morning when the place opens!! Thank you.

Get yourself a nice drop checker off of Aquabid along with a Reference kH solution from Billionzz... It works great as a visual warning that your CO2 is out:

AquaBid.com - Your Aquatic Auction Website

AquaBid.com - Your Aquatic Auction Website

actually I went on ebay as soon as Vaughn mentioned them.. hadn't kept up on those threads before.. do you leave the checker in or just use it on occassion.?

So when you think an dsee other folks claming that their CO2 is fine and that they are positive it cannot be that, you'll know why and how I say what I say.

Regards,
Tom Barr

You can either leave the drop checker in the tank, or take it out, drain the fluid out of it, and set it up again whenever you want to check the CO2 again. Since the latter is a lot of work, why not just leave it in the tank? You could put it in an inconspicuous location in the tank, then move it out where you can see it easier when you want to use it. If you left it out of the water very long the solution in it would begin evaporating, which would raise the KH of the water in it.