First Question - Food and Drain Standpipe

[Phillip Townsend]

I'm setting up a basic flood and drain system inside a solar greenhouse--fish tank dug into the floor, grow beds above, and a timer that will run the pump approximately 15 minutes on followed by 45 minutes off.  The supply pipe filling the bed is 1-1/4" PVC.  Should my overflow standpipe drain also be 1-1/4"?  I know that I need holes around the base of the pipe to allow slow draining, but how do I figure how many holes I will need, what size they should be, and how close to the bottom of the bed they should be?  (My fish tank has a capacity of 900 gallons, and I have three grow beds, each with a capacity of about 300 gallons, one pump, and an indexing valve to alternate which bed is filling.)  Thanks for any help and guidance you can share.

[George]

Jeff, that is truly a scary thought but my pipes are glued and the pump is raised from the bottom of the tank.  I've experienced the unexpected a few times but not that, not yet.  I may raise my pump further, enough to keep a couple of hundred gallons in the tank, should a leak occur.  I really like my tank in the ground so that, coupled with the fact that it would involve a lot of work, rules out a system redesign at this point.  

Jeff S said:

Without a sump how do you keep from pumping your fish tank dry if you have a leak when you aren't around? It's happened to me twice. Fortunately with the sump I just emptied the sump.

 

[Jeff S]

If/when you do a redesign be sure to put your air stone at or near the bottom so the fish will also get air. I lost fish once because the water pump kicked the GFI and the air was plugged into the same circuit.

George said:

Jeff, that is truly a scary thought but my pipes are glued and the pump is raised from the bottom of the tank.  I've experienced the unexpected a few times but not that, not yet.  I may raise my pump further, enough to keep a couple of hundred gallons in the tank, should a leak occur.  I really like my tank in the ground so that, coupled with the fact that it would involve a lot of work, rules out a system redesign at this point.  

Jeff S said:

Without a sump how do you keep from pumping your fish tank dry if you have a leak when you aren't around? It's happened to me twice. Fortunately with the sump I just emptied the sump.

 

[Sacred Valley]

phillip. I always say drain with a larger pipe then you supply. Also, the holes and timer method is way easier than bell siphon. Depending on how many siphons your running, i was always playing with mine and thus made them not worth it (i had to have 8 going at once). SO, experiment with the holes. Just sit there and watch. Start small and drill larger if needed to drain all the way before the pump comes back on. Also, the more you circulate the water the better. You'll have more bio filtration and greater O2 levels. If your have lots of waterfalls and water moving around you'll have lots of o2 and you'll never see any root rot or anything of the likes. hell jon parr runs dead end beds, which seems to disqualify any concerns from many new AP users. I run my timer 45 on 15 off in the day time and 45 off and 15 on at night to save in heating. My standpipe holes are such that my deep media ibc tanks (where i have the standpipe) fill in 15 minutes and drain in 15. The overflow for 30 minutes in the day time is no problem because i have so many waterfalls and water moving through shallow media beds that the o2 has plenty to spare. 

[Jim Fisk]

Keep in mind guys that with timed F&D if you are only filling once an hour (which is fine) you don't have "lots" of water running around so I would certainly add an aeration air pump. Much of your design depends upon your fish species. I raise Trout (delicious Trout;-) and they require constant flow so my five 1" dia stand pipe by 12" high bell siphons are really a necessity and they have been running continuously for 4 years now without any "playing" with them whatsoever. None, nada. SO it might just be in the design? I have now built and sold well over 1000 siphons shipped worldwide and still have 100% positive feedback from enthusiastic customers so don't be afraid of bell siphons if you feel the need. They are totally passive and do their thing year in and year out and I have one pump in a buried 275g sump where it never gets plugged up with fish waste and feed solids and I still have a septic tank style float switch just in case. My new Grech 2100g pump has been amazing and at half the price and half the wattage of my former pump (3 yrs it ran until it died of old age and the rebuild kit was close to the price of the Grech, so...) they are a real bargain. You can find them on eBay. I purchased the larger one (I really only need a 1200g) at 10$ more ($50.00 delivered!!) because at the price I couldn't believe the specs. Well I am here to say their specs are correct and now I run the bypass wide open and the pump turned all the way down and I still have more flow than I need but more GBs are coming beyond my wicking bed that has been working great (also on a short bell siphon). SO, my input. Here is a pic of the wicking bed using compost and I highly recommend trying one.

[Jeff S]

 I was thinking to myself "where's Jim the siphon guru?" Haven't seen much of you lately. 

[Don Cole]

I have a simple timed system. 900 gal fish tank and two 4x8 growbeds. My grow beds are supplied by a 1.5" line from a 3600gph pump. The timer is set to fill in ten minutes and they drain in 4 minutes. The drain is a 1 1/4" bulkhead fitting with no riser just a gravel guard.the drain from the growbed is transitioned to a 2" pipe tha carries the water to one of the fish tanks. I dont use a sump. I have three 300 gal. fish tanks connected together with the pump in the first and each growbed drains into a different fish tank. I get a lot of mixing of the fish tank water this way for good circulation.

[Jeff S]

George,

You could easily attache a float switch inside your fish tank about halfway down or higher so if your water level drops it would turn off your pump. They're about $16 at the big box.

George said:

Jeff, that is truly a scary thought but my pipes are glued and the pump is raised from the bottom of the tank.  I've experienced the unexpected a few times but not that, not yet.  I may raise my pump further, enough to keep a couple of hundred gallons in the tank, should a leak occur.  I really like my tank in the ground so that, coupled with the fact that it would involve a lot of work, rules out a system redesign at this point.  

Jeff S said:

Without a sump how do you keep from pumping your fish tank dry if you have a leak when you aren't around? It's happened to me twice. Fortunately with the sump I just emptied the sump.

 

[Jim Fisk]

Hi Jeff, in a word "busy". To be honest the robust conversations are on FB these days. Many, many AP groups. I try and help out here when I can. Over 1000 siphons delivered out of our little shop. I build and Lynne ships.. Fun but still not at a living wage level. Helped hundreds of folks get their systems up and running tho and that's what it's all about.

Jeff S said:

 I was thinking to myself "where's Jim the siphon guru?" Haven't seen much of you lately.