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foodchain
11-16-2011, 12:10 PM
How densely stocked are your fish? I may have missed it, but I don't think we have narrowed down your species. Some species are tolerant than others. Just my opinion, but I think you would want to have a little extra grow bed for filtration than the bare minimum. Keep in mind 50 little fish produce far less waste than 50 big fish.

Russian Trout 17
11-17-2011, 08:16 AM
oh yea. yellow perch it is looking like, it gets cold up here in syracuse and they sure wont mind as much as other fish. have you ever heard of grow beds being stacked up onto one another? or is that silly. im trying to save as much space as possible, for 2 of there 956 gall tanks its gonna be a lot of grow space... and i still have to squeeze in a seed table for the lil ones waiting to be transplanted.

foodchain
11-17-2011, 08:33 AM
You can sort of do it that way, but enough light has to get down to the bottom ones. So it's more of a terracing. Not vertical like shelves unless you are providing the light. Providing the light though drives up costs, so I don't do it. You can try verticle grow beds like used in hydro...I have tried verticle pvc pipes for strawberries, but had better growth and frutiing with gutters. They have shallow roots and benefit more from the heat.

keith_r
11-18-2011, 07:33 AM
check out growing power, they have "bunk" beds..

newimaging
12-25-2011, 11:16 PM
Here is a newbie question:
Why could`t you use growing beds as bio filters and add them ahead of the NFT lines ?
Or would it deplete to much of the nutrients.
Maybe the other way would be to filter out the solids, then go through the NFT and then biofilter with the grow beds ?

Christian

keith_r
12-27-2011, 08:41 AM
it should work, but you have to make sure you don't have solids exiting the gb's into the nft's..

i just re-read this thread.. regarding fishfood's comment;
"How densely stocked are your fish? I may have missed it, but I don't think we have narrowed down your species. Some species are tolerant than others. Just my opinion, but I think you would want to have a little extra grow bed for filtration than the bare minimum. Keep in mind 50 little fish produce far less waste than 50 big fish."

smaller fish actually eat more than larger fish, and are more active (expelling ammonia from their gills) - something someone with an aquaculture background said is to think the small fish like teenagers, always hungry and growing..
i know most of the stuff i've read on feed rates is that smaller fish are fed a higher percentage of their body weight
i've seen backyarders that think that stocking with fingerlings will not cause an ammonia spike because the fish are so small but they find out pretty quickly that it's not the case..
it's important to monitor the system early on.. i don't test any where as near regularly as i did when i started