Backyard Aquaponics
A place to discuss aquaponics

Hey everyone so I've been chillin in these forums for a while, having my googled questions answered by the fine folks here and I figured its time to say hello! For the past few months I've been digging a huge hole in my yard with the intention of making a beautiful yet functional aquaponic pond. I just purchased a 20ftx25ft epdm 45 mil liner and am laying down carpet as padding. I've hit a bit of a snag though as I calculated the volume of my pond to be roughly 3500 gallons and I've read here that anything under a 1:2 ratio for bed to tank is insufficient for filtering. My original plan was to build three 4'x14'x1' beds and push water through at about 3000gph. However, after looking at the cost of media I may only be able to afford one bed to start with. Would a 420 gallon bed stand any chance of filtering 3500 gallons of fish pond? I don't plan to stock very heavily though I am going to go ahead and purchase an aquanique 3750gph pump to move the water up my 7' rise to the bed(probably 2500gph all said and done). Whadaya say folks, am I in way over my head? My pond is just over 6' deep at the deep end! I'd like to be able to swim in there occasionally too, is that crazy?

..
Crap - no idea where you got the No-Go with the Water to Bed ratio..

It has everything to do with the FISH to Bed ratio, and the common quoted figure of 30L per fush is the norm. I am guessing that equates to about 5G per Fush..

It is the Fish POO etc. that dictates the filtration needed...


but then you have rule-rebels like me who re-write the rules and have 2L of media per fish (and near no plants), but with solids removal and annoxic nitrogen removal..
..
.

Hi AquaphonicDude, that post slipped past the keepers.

Natural ponds/pools don't have AP systems attached

So if you incorporate other things with your pond, including gravel/stones in the bottom and actually have plants in it at one end of something then you will basically run your pond as a pond and then have some grow beds on the side to make use of nutrients etc.

You will probably still need filtering with your pump and can look at options for that in the swimming pool scale stuff.

If you look around here there are a few swimming pool conversions (search swimming pool).
they should give you some ideas.

be careful with rules - they often relate to a specific context or post or type of system, and may have nothing to do with what you are planning to do. Basically (as Buidoi says) the need for filtering is dependent upon the actual amount of ammonia and waste solids that needs to be processed. If you dont have enough and the system starts getting overwhelmed then you need to look at an additional or more appropriate option.

outside of AP, I think there are places around the web about converting swimming pools into natural swimming holes.
There are some health type issues to consider....

and also places about converting swimming pools into fishing holes (aquaculture ponds).

presumably your Google searches have turned these types of things up.

some in your CA backyard...
http://permaculturenews.org/2011/10/28/ ... ss-report/
http://permaculturenews.org/2009/07/21/ ... fish-farm/

Will a 7' head height be a factor in getting water turned over?

3750gph would seem like it would turn over that amount of water in an hour but that's assuming it's a constant flow. Planning to use siphons in the grow beds?

its not viable that he run it on AP lines, far outside the practicality of that and AP rules of thumb become immaterial.
ie. why would you need (or even bother) to turn over a whole volume in 1 hour ?

there are other ways to have a living pond with active bacteria and water plants, and the AP could then just tap onto that.

Indeed , when you start talking about large ponds, the AP rules have little meaning, as the can be so much bacterial actin , just in the water..

I would imagine that the problem with converting to some kind of Bio-Pool with plants etc., is that you may find the pond plants use all the nutrients..

I could imagine that removing the solids would be an issue with a large pool/pond..

But if you were planning a pond liner anyway, you could sculpt the base with sand to create a suitable depression, and then remove the solids to an external process and Hydro-Ponics..
That is what I would be doing, and thus make a feature of the pool itself..

going back to the rules (wot likely don't apply), the recommendation is a pool turnover of something like 1Pool Volume per our, but that would mean that volume through the GB per hour.. and that would be just crazy, meaning you then need a significant grow-bed-bypass..
..
.

Roger that.