Backyard Aquaponics
A place to discuss aquaponics

HI all, our school system is growing pretty good. Recently we have had a hair-like fuzz growing over our gravel. Its preventing seedlings from growing well. Any ideas how to get rid of it? Anyone know of any fish safe fungicide?

Thanks all

i'm interested in this question as well. i have indoor AP system, and it seems to me that moist GB would be a haven for mold.

Sounds like you are flooding too high. Lower the growbed water level, and increase ventilation, and light.

Are you sure it's not an algae rather than a fungus.... as OBO says ...

Is this a dark fuzzy dusty fungus or a fibrous wet mat?

I had enough underwater fungus in my system growbed at one point that it pretty much locked a large area of gravel into one mass. I didn't check the thickness, but it was at least a couple inches. I think it was feeding on excess food sucked out of the FT. After a month or so it disappeared without us taking any specific steps against it, possibly as the ecosystem evolved.

Possible solutions:
reduce waste food
wait a bit...perhaps add worm castings to add some useful organisms to the ecosystem
change from constant flow to timer flood/drain (I didn't, but did try to shift watering spots so they were not
constantly flooded.)

Additionally, our plants were growing well, so may have been able to deal with it as adults rather than as seedlings.

Ok the fungus is like fine white hair growing from the gravel. I'm not sure its fungus but it looks like it. I dunno...

Ok some things to try. I am already running pumps on 30 minutes, off 1 hour. I could reduce the on time or increase the off time. I was also thinking of letting the GB just dry out for a day or something.

The funny thing is I have an identical system and its fine. So somehow this fungus was introduced. Maybe from the strawberry plants. Anyhow no seedlings will grow because of it.

HN

OK after a little reading I found out we most likely have a fungus and "damping off" is occurring. Any ideas on how to manage? I will reduce water in the GB.

Dossier for Potassium Bicarbonate in Crop Production
Prepared by Zea Sonnabend, policy advisor to CCOF Inc.
Draft 2 5/17/06

Potassium bicarbonate is a safe material for control of several important fungal diseases of grapes, strawberries, tomatoes, and cucurbits. It is allowed for use but the USDA NOP in organic production because it has meets all of the evaluation criteria satisfactorily.
Specific Uses: Disease control of powdery mildew (Sphaerotheca fuliginea) on cucurbits and (Uncinula necator)on grapes, early blight (Alternaria cucumerina) on tomatoes, and mold (botrytis spp.) on strawberries. Potassium bicarbonate is used both as a protectant and as an eradicant for powdery mildew on grapes, and is also labeled for use in control of downey mildew (Plasmopara viticola).
Action: Bicarbonate ion has been identified as the probable cause of growth inhibition in some bacteria and fungi. The bicarbonate causes the collapse of hyphal walls and shrinkage of conidia (different parts of the fungus). In addition, pH elevation may also play a significant role. Bicarbonates can eliminate the disease after it has already appeared on the crop, unlike other conventional controls that are preventative only.
Combinations: Recommended to be used with a coating polymer to help provide uniform coverage of leaf. (Research this for both plants and fish.)
b) Degradability
Decomposition products are potassium carbonate, water, and carbon dioxide. These materials readily dissipate inthe environment.

You do have to be careful in raising the pH too high and because it degrades to carbon dioxide, you need to be careful of depriving oxygen to the fish but all respects it is similar to calcium carbonate so use the same care. The bonus is the addition of potassium for the plants after break down has occured.

Yep, great product... marketed here in Aus .. as "EcoRose"... a certified organic input...

Benefits... potassium... and a carbonate buffer...

Been singing its praises for a while.. but not a lot of people seem to have picked up on it... except on another forum (where they seem to claim they found it ... )...

Have since found a "bulk" source... try your local winemaking supply companies...