"Black weed" and the refugium... Calling all 'fuge experts!

A couple of weeks ago I set up a 50 gallon refugium for a hundred gallon african cichlid grow out tank. I'm hoping to reduce nitrates and phosphates to a point where water changes become quarterly rather than monthly.

For me this is important because I want to maintain dissolved mineral levels in the system consistant with Lake Milawi without having to spend a lot of time and money doing water testing and chemical addition.

I'm using java moss and ghost shrimp for now, since I have a good supply of the moss from my 100 gallon grow out tanks, although it looks a little blanched from lack of light at the moment. The new growth is the characteristic emerald green of healthy java moss.




As you can see from the pix there is also a healthy crop of black weed beginning to develop from the moss that I had previusly woven onto eggcrate lattice.

At this point I'm not overly concerned about apearance, my goal being water quality enhancement from the 'fuge. Does anyone have any experience with this type of setup that can tell me if the black weed will overtake the java moss and destroy my refugium's positive impact. So far the set up has been very effective in lowering nitrates. I have yet to test for phosphate levels.

I run the lighting (100 Watts flourescant grow lights) 18 hours a day. Should I be using more or less light, for longer or shorter a period of time.

What kind of lighting favours the black weed (cyanobacter?)?

I introduced 20 ghost shrimp into the refugium after it had been running a couple of days. I've always wanted an invert collection but as a fishkeeper, I could never keep them long before the fish estroyed them.

They are interesting to watch, being very busy, ornate and so gossamer in their construction. It apears by the colour of their gut that they will eat the black weed, although I would need several hundred of them to make any real impact on what I currently have...



Does anyone know what the population doubling time is for these shrimp? I know they make excellant feeders and that they are prized for just that at my LFS.

WOW...the response to my cry for help is just...well overwhelming. Can anyone recommend a a site where people actually get involved and help each other solve their problems?

MFK aint what it used to be...

JoelR;2362784; said:

The only way I've been able to get rid of green slime algae is to use algae remover chemicals and a black out. That is some nasty stuff.
One thing you might want to try is some amo shrimp (sp?) They are much better algae eaters than ghost shrimp.

Other than that, ????? Good luck.

Click to expand...

Any problem mixing the two kinds of shrimp? I would prefer not to remove the ghost shrimp...

Hmmm....Thanks Cassharper for helping out. Much apreciated. Since its a 'fuge, I'm not worried about cyanobacter growing in it as long as it doesnt interfere with the other plants and beasties living there.

Any harm in letting it be? Presumably once the nitrates come down, it should begin to flag a bit and may disapear of its own acord.

What about a CO-2 system to give the moss a leg up? Will that have an impact on the black weed? I prefer not to move the shrimp. The lid on that tank fits like a condom and its a bugger to get off!