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Dave and I have been playing with a barrelsystem 2 grow beds a fisf barrel and a flushbarrel. so far all we have grown is LG. We use black granite which increase the pH 8.3 we are going to have to use a different medium my normal to have well wtater here is 6.4 also I think the algae is eateing everything up so I have some questions first how many gold fish in a 55 gallon barrel does it take to create  enough ammoniato start my system propagating ?I have about 30 goldfish in there it doesn't seem to be enough I have no nitrates no ammonia no nitrites and what little is growing in my bbarrel looks like a starving to death


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I used ammonia to start my system. Fish should come later. Please read the primer here


  How big are your gold fish and how often do you feed them.  In a 55-gallon barrel FT you have about 35 - 40 gallons of water, Iam assuming.  You need to add more fish to your system for the ammoinia to increase.  Also remember with a pH of 8.3 you are severily damaging your fishes gills and restricting the nutrient uptake of your plants.  Using the black granet that makes your pH rise will drive you crazy trying to constantly lower it.  If you are using citric acid to lower the pH may be another problem you are facing.  Try to find some phosphoric or nitric acid, the plants will appreciate the minerals.  OR - go on line if not near a hydroponic store and purchase "pH down".

  You stated that you do not have any nitrates, ammonia or nitrites.  This indicates that all the Ammonia and nitrites are being converted to nitrates but the ammount of plants are using it all.  Decrease the ammount of plants, increase the ammount of fish and lower your pH.  This will substantially increase the Ammoniua and nitrite in your system allowing the bacteria to convert more of this into nitrates.  Try to find a medium that is pH nutral if possible.  I have access to purple quartzite which is pH nutral.  You may want to change over to LICA or lavarock, I usually do not recomment the lavarock as it is hard on the hands and roots of your plants.  

  All this is my assumption, we may need more info to do a proper identification of your problem.  Are you using the proper grow lighes, size in cubic feet of the grow beds, ammount of usable water in your system, size of the fish, what and how often do you feed your fish, what type of LG are you growing.  All these will help us help you.

I'm growing plenty of algae ( not LG I have a bad habit of using voice recognitiont)

 that's because I got the system outside for right now so its getting plenty of sunlight I do believe the problem is mainly the black granite so I'm going to have to switch to something else I could probably put rounded river rock in their small pebbles and uh a little bit of the granitic the pH naturally is about 6.4 I mean if I can't get a barrel under control about how can i graduate to a bigger system. how many goldfish would you recommend for 50 gallon barrel on how much would you recommend that I feed them?

thank you for your advice kim


  I am in agreement with the rounded river stone, even though there is less surface area for the bacteria to grow on it, it is still a usuable media, especially since Hydroton and expanded shale are so expensive.  With proper pH control, 6.4 is not that far off.  A few pieces of the black granet in a bag may help with the pH.  I, personally wouldn't just through the granet in with the pebbles as they may get lost and with them in a bag, you can remove or add to them to get a handle on the pH.

  In a 10-gallon FT, I had 5, 4-5" goldfish and my barrel system did very well.  With this in mind, figure the size or length of your present goldfish and calculate how many you would need to average say 15" of fish per 10-gallons of water.  Multiply this length or amount of fish with the total gallons your system holds.  I must admit this is a rough guestament of the amount of fish you need so use your best judgment.

I have 40 goldfish (4" long) in 280 gallons and I'm getting enough nutrients to supply 3 3X5 grow beds fully planted.  I would think the pH is a big factor.


  HAve you checked the pH of your water??  As long as it is within 6.8 - 7.4 you'll be OK.  What are the other numbers reading?? Nitrite, Nitrates, pH and Ammonia.  What are you using to test the water?


I keep my pH around 6.4 to 6.6.  All numbers are good.  I use a master fish test kit.  I was responding to the person with the with the black granet.  I think her pH is what is making the plants unable to access the nutrients.  I wonder if more fish is really necessary?  That was the intent of my post - to say I have the same number of goldfish in much more water and am doing just fine.  I realize what is clear to me is not when read by others.

Leo White Bear said:


  HAve you checked the pH of your water??  As long as it is within 6.8 - 7.4 you'll be OK.  What are the other numbers reading?? Nitrite, Nitrates, pH and Ammonia.  What are you using to test the water?


Leo when you say put thr black granit in a bag would it be better to drop the bag in one of the

 water units as aposed to putting it in with the grow medium? I think now that we know that we have the system up we are going to start over in the spring. Give us this winter to clean everything out and start over. What do recomed to keep the algee down.



yes, put a couple of handsfull in a bag and suspend it in the FT water.  The limestone in it will dissolve and affect the pH, that is if this is the major cause of your pH difficulties.  The best way to keep the algae down is to blacken or darken the sides of the FT.  You can either paint it with a plastic paint made for lawn chairs or use black trash bags to line the outside of the FT.  Also if you can cover the tank with slats of some sort this will help to keep the light to a minimum.  Now algae is an indication that you have a very nutrient rich water and probably need to add more grow bed area.  If you see the brown slime on the sides of the FT, this tells you that bacteria are strong and healthy and are doing exactly what you want them to do, colonize all areas that they possibly can.  I know the sinking feeling of having to dismantle your unit soon as I have to do the same towards the end of October and bring my fish indoors.  I can't wait until my barn system is up and running, at least those units are in a heated barn.

Leo you are always so nice in helping everyone.

Thank you very much



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