Gammarus

[Khmer Aquaponics]

Hello! Has anyone got this guy in the system?  This little guy has done a great job at Friendly Aquaponics ,and now I doubt how this little guy exists in their system. 

[Keith Rowan]

i've got tons of them, with 3 10 gallon glass tanks devoted to raising more..great snack for small yellow perch (i can harvest hundreds at a time)

any filter i've made/used has eventually filled with "scuds", my gravel beds don't drain completely, and i know that there are plenty in every bed..

[Jon Parr]

Likewise, Keith. Scuds are to AP as worms are to soil. I recently toured a commercial AP raft system, up and running for 3 month with ALL solids made completely soluble by scuds. No filters, no settling, no maintenance, just scuds. I now add them to all systems. Khmer, why do you doubt they exist at FAP?

[Christian James]

How are you raising them in the 10 gallon tanks?  I've got some in my aquaponics and tanks / mini ponds but nothing near what Friendly has, pretty just a few here and there in the roots. 

[Khmer Aquaponics]

Well, I just wonder how you and the guys at Friendly AP introduce them into the systems. I mean where all of you can find or get those little guys. I don't know where to find them in Cambodia. However, according to what I have read it is said that those little guys exist everywhere in the world. What does "Scud" mean? Have you got any suggestions for me to easily find them? 
Jon Parr said:

Likewise, Keith. Scuds are to AP as worms are to soil. I recently toured a commercial AP raft system, up and running for 3 month with ALL solids made completely soluble by scuds. No filters, no settling, no maintenance, just scuds. I now add them to all systems. Khmer, why do you doubt they exist at FAP?

[Khmer Aquaponics]

Here, we have another type of aquatic insects that looks different from Gammarus. However, due to my observation, I noticed that they are also fish-poo eaters, but I don't know the name. They have a bean like body. 

[Keith Rowan]

scuds are a general name for gammarus.. there are many different species all over the world..

you'll need a fine net if you try to gather some in the wild..

i purchased mine from a website called aquabid, it does have members all over the world, so you could check there..

i bought a mix of daphnia and scuds from a pond supplie place once as well.. after dumping the contents of the bag into the ft i never really saw much of them until i pulled apart a filter that was leaking, and found hundreds crawling through ths scrubbie pads.. i had 10 gallon tanks setup for daphnia so i a just shook the pads into the tanks, i left a few scrubbie pads in all three tanks because they seem to like them..  i feed the tanks cuttings from my growbeds, and when i want to harvest any, i can pull out a plant leaf that will be covered with them.. carry it over to the ft, and dump in.. the yp and bg go nuts for them, even though they are small.. the largest i've seen has been around the size of a grain of rice..

meanwhile, i've got a bunch of marmokreb babies, growing fast on bloodworms, beefheart carrots and peas!

[Khmer Aquaponics]

Thank so much Keith for your information. I will have a try!!!

Keith Rowan said:

scuds are a general name for gammarus.. there are many different species all over the world..

you'll need a fine net if you try to gather some in the wild..

i purchased mine from a website called aquabid, it does have members all over the world, so you could check there..

i bought a mix of daphnia and scuds from a pond supplie place once as well.. after dumping the contents of the bag into the ft i never really saw much of them until i pulled apart a filter that was leaking, and found hundreds crawling through ths scrubbie pads.. i had 10 gallon tanks setup for daphnia so i a just shook the pads into the tanks, i left a few scrubbie pads in all three tanks because they seem to like them..  i feed the tanks cuttings from my growbeds, and when i want to harvest any, i can pull out a plant leaf that will be covered with them.. carry it over to the ft, and dump in.. the yp and bg go nuts for them, even though they are small.. the largest i've seen has been around the size of a grain of rice..

meanwhile, i've got a bunch of marmokreb babies, growing fast on bloodworms, beefheart carrots and peas!

[Gina Cavaliero]

Actually scuds, ghost shrimp or gammarus do not proliferate anywhere.  We have never had any appear in our systems and even upon trying to introduce them, they did not flourish and populate the system.  We and others have deduced that they are quite dependent upon the mineral content of your water supply and will appear in some systems and not in all and much of it may be related to Calcium content as they are a crustacean.  I don't know this for certain, but that is our hypothesis.  

We are actually now relieved that our gammarus "seeding" was unsuccessful.  We have now learned that in some cases, they have been reported to overpopulate and when not enough fish waste is present, they will begin to feed on plant roots.  In a commercial system introducing an organism with no means of regulating it could certainly be a problem.  They may be an option in some geographic areas for waste eradication, but a commercial system with no solids containment provision could be disastrous if one later finds that this organism does not inhabit the system as expected.  In fact it was even problematic in our small, low density backyard system that had no solids filtration and we have since modified it to rectify the problem.       

[Chris Smith]

I have gammarus thriving in one of my systems but will not get well established in my big system. I have tried seeding my big system many times with then without success. I cannot figure out why they will do so well in one system and not in another. The main difference in the systems is that I made concrete tanks for the big one. Gina your hypothesis is similar to mine. I have been thinking the lack of population has something to do with mineral content but I never considered it was specifically related to calcium.

Khmer, my gammarus originally came from Friendly so I can assure you they do exist in their systems. Gammarus is reported to live around the world and may be in a local steam or river. I have found them in the wild in slow moving streams with good unpolluted water. They love to eat dead organic stuff so look for decomposing organic matter in your local stream and you might get lucky. Beware though introducing things into your system may not give you the results you expect. Introducing things from the wild always has a chance of allowing hitch hikers in you may not want!!

[Khmer Aquaponics]

" Thank you Gina and Chris for sharing your gammarus's stories. These little guys really concern me. I'll find my way to get them into my system. But getting them form the wild could be a big problem, I see.  "
Chris Smith said:

I have gammarus thriving in one of my systems but will not get well established in my big system. I have tried seeding my big system many times with then without success. I cannot figure out why they will do so well in one system and not in another. The main difference in the systems is that I made concrete tanks for the big one. Gina your hypothesis is similar to mine. I have been thinking the lack of population has something to do with mineral content but I never considered it was specifically related to calcium.

Khmer, my gammarus originally came from Friendly so I can assure you they do exist in their systems. Gammarus is reported to live around the world and may be in a local steam or river. I have found them in the wild in slow moving streams with good unpolluted water. They love to eat dead organic stuff so look for decomposing organic matter in your local stream and you might get lucky. Beware though introducing things into your system may not give you the results you expect. Introducing things from the wild always has a chance of allowing hitch hikers in you may not want!!

[Keith Rowan]

here's a little "scud experiment" to give you an idea of what these things can do..

i put a zuchinni leaf in each of my 3 scud culture tanks sunday afternoon, around 12:30

 

 

[Keith Rowan]

i harvested pretty heavily on saturday, and started these sunday..

monday evening, around 7:30 here are what the leaves look like