So after reviewing the spacial and weight limits of my apartment's wooden balcony I have decided to build a tower system. So far I'm hooked on Zipgrow towers and while the the system is a little bit out of my price range I figured I could improvise and build it out of 3" pvc pipes with bio filter media(1.5" thick mesh filters used for ponds)
My concerns are the following.
1) I believe my balcony can only hold 5-700lbs. a 55 gal barrel=458lbs. If I use half the barrel for my Fish Tank and the other 1/2 for my Sump-Tank will I have enough waste to grow three-four 3' pipes?
2) how big should my sump tank be in relation to my fish tank? If I can have 3/4 of the 55g barrel as my FT and 1/4 for the Sump than that should help relax the waste issue right?
3) Pump: for anyone who has used towers before do you have any recommendations as far as pumps are concerned? (ie. which is better inline or submersable)
4)What do u think of my system any concerns questions? Here's the diagram
p.s. if anyone is interested Zipgrow has a huge video archive of ideas for general and tower AP growers.
You will have plenty of nutrients for your towers and possibly even a small grow bed as well. You could use a portion of the barrel for the bed. I have had success with the 8" x 16" flower trays from Home Depot as well. I have a barrel system that is perfect for balconies. http://www.newstreamsaquaponics.com/products/aquaponics-garden-syst... I currently have over 20 plants growing in mine at home.
Good luck on your build!
re: question 2: I think what's critical is ratio of sump to growbed, not sump to FT. The way I figure it is: if you're doing a flood-and-drain system with constant water height in your fish tank, your sump volume needs to be a bit more than the difference in volume of water in your growbed at maximum and minimum points. For example, if your gross growbed volume is 50 gallons, and you fill it with some kind of media, the media might take up something like 1/2 the volume or 25 gallons. That means when you fill the GB with water, you're adding about 25 gallons of water. And let's say with your autosiphon you're able to drain all the water out of the GB. That means your sump will need to absorb that volume of water, or 25 gallons. But in the other part of the cycle, when you've pumped enough water out of your sump to fill your GB, you'll still want some water remaining in your sump to cover your pump, assuming you're using a submersible pump. So, sump volume should be greater than 25 gallons by the amount necessary to cover your pump, plus some extra to allow for evaporation etc. Kapisch?
re: 3: I've seen both submersible and external pumps used for towers. I have some limited experience with towers from State Fair exhibit last summer. Main takeaway for me was realizing that the extra pumping capacity required for towers (due to their height) is significant. Takes a lot more juice (electricity) to make use of vertical space (ie use towers) -- you don't get something for nothing, unfortunately.