The rocks? The PVC size?

[Adrena lee]

I have found Meramec C Gravel, but I'm not sure if it good to use in my grow beds?  Also I am not exactly which size PVC pipe to use. 1, 1 1/2 , or 2 inch. I can't afford any mistakes in these supplies right now so someone can help I hope. Thanks so much.

[Adrena lee]

Thank you Brandon.  2 inch PVC is what I'll use then. I am getting the pipe and the gravel tomorrow so I can get this project started.

Brandon Koots said:

I don't know about the gravel. But I suggest to use 2 inch PVC pipes.

[Adrena lee]

I wanted to, but I am about out of money. That is more expensive than the pea type gravel, and I have 5  55 gallon barrels split in halves that I have to fill.I found the gravel for 93.00 for a yard and a half with delivery included. I have no idea how much the hydroton pellets would cost. I saw them in small amounts for high price compared to how much I need. But no I don't have it yet.

Brandon Koots said:

If you don't have the gravel yet, maybe you can buy Hydroton instead? That's what I use. It helps balancing the pH level and the temperature.

[matt]

What is the PVC for? What type of system are you going for? Flood and drain? How are you making it flood/drain, a bell siphon?

2" PVC moves massive amounts of water, I doubt you will need that much flow, especially if it is the inner tube in your bell siphon. What is the rating on your pump (gallons per hour)? 1" PVC will work in almost every home aquaponics situation unless your moving large volumes of water, or your worried about clogging, or you want to be able to clean it out better. 2" PVC and parts are twice the price or more so if you don't need it stick with 1"

 

The gravel in your picture looks almost perfect as for size. Personally I prefer a little rounder, since it normally makes more space for roots and air in between the pebbles. The very best is volcanic type of rocks IMO similar to lava rock, light and filled with air pockets, but still stable in water for decades. But as you can imagine its not easy to come by :)

[Adrena lee]

Hi Matt. The PVC is for running from my grow beds to my fish pool. I have a fish pool that is 4 ft wide, 8 ft. long and about 2 1/2 ft deep. Ebb and Flow is the way I'm doing it. I am getting a water level thing, lol so that when it gets to a certain level the water will drain.  I am getting a flush for it like you use on a toilet that I saw used on a you tube video. I really am learning as I go. Now there is a gravel that is a little smaller, it's called pea gravel, but I thought it might be too small, is there such a thing as too small for the rocks?

matt said:

What is the PVC for? What type of system are you going for? Flood and drain? How are you making it flood/drain, a bell siphon?

2" PVC moves massive amounts of water, I doubt you will need that much flow, especially if it is the inner tube in your bell siphon. What is the rating on your pump (gallons per hour)? 1" PVC will work in almost every home aquaponics situation unless your moving large volumes of water, or your worried about clogging, or you want to be able to clean it out better. 2" PVC and parts are twice the price or more so if you don't need it stick with 1"

 

The gravel in your picture looks almost perfect as for size. Personally I prefer a little rounder, since it normally makes more space for roots and air in between the pebbles. The very best is volcanic type of rocks IMO similar to lava rock, light and filled with air pockets, but still stable in water for decades. But as you can imagine its not easy to come by

[Adrena lee]

Thanks Brandon. They do have a smaller rock , pea gravel. It's 3/8 inch in size but I thought it may be too small, any thoughts?

Brandon Koots said:

Ok then. It won't be a problem for the plants. 

Success with your system!

[matt]

pea gravel will work, but it will be a poor medium for most plants I would imagine since it has smaller root  and air space. The larger stones in the picture will work better then pea gravel. The only thing you could do to get better medium is either find a smoother version of same size pieces, or a lighter more airfilled, but still  water stable rock. If i scored the rock in your picture for how well it fits most aquaponic systems I would give it a ~75/100. Pea gravel for me gets a score of 60/100.

I strongly suggest against using a toilet type system for flood and drain. I have seen them on youtube. They are more prone to failures open, and closed. Either failure can be very hard on your crops or fish and possibly pump and other equipment. Bell siphons or timers are better choices for reliability. If you really want a flush system a emergency overflow is a MUST.

[Adrena lee]

Ok I think  I'll go with the C Gravel, I like the odds better. I will see about getting what I need to do the Bell siphons or timers. I knew I needed an emergency overflow, but I don't want to chance it. I am going to start with gold fish only so if I have problems in the beginning it will be easy to take the loss, and then later get Tilapia and some other type fish. I really appreciate all the help and time you have given me.
matt said:

pea gravel will work, but it will be a poor medium for most plants I would imagine since it has smaller root  and air space. The larger stones in the picture will work better then pea gravel. The only thing you could do to get better medium is either find a smoother version of same size pieces, or a lighter more airfilled, but still  water stable rock. If i scored the rock in your picture for how well it fits most aquaponic systems I would give it a ~75/100. Pea gravel for me gets a score of 60/100.

I strongly suggest against using a toilet type system for flood and drain. I have seen them on youtube. They are more prone to failures open, and closed. Either failure can be very hard on your crops or fish and possibly pump and other equipment. Bell siphons or timers are better choices for reliability. If you really want a flush system a emergency overflow is a MUST.

[matt]

Great idea to start with goldfish. Bell siphons are better then timers as for reliability. Pumps have this bad habit of sometimes not starting after they are turned off and on. The worst failure you can get for a flush system is the open failure because it makes the bed never flood. In hot weather your crops can be dead in a day, or severely stressed.

[Tom Barnhardt]

You might also want to look at a loop siphon with a timer. This is what I am using in my test system and no problems yet.

 

[David Waite]

Adrena looks like your rock is 1/2 to 1 in size. I like that size in my beds it works great.  I am using koi for fish and really like them. Very hardy. Dont buy feeder gold fish as they are a sickly lot. Definitely use timed or affnan siphons . for ease of construction a timed system is easier. Affnan siphons can be a little tricky to the newby. Take lots of pics and post and these guys will jump thru hoops to help ya. Good luck. Sylvia sells siphons and timers here in her store.

[Adrena lee]

Thanks again. I am going to order the C gravel in the morning and hunt down a Bell siphon. You have been very helpful.

matt said:

Great idea to start with goldfish. Bell siphons are better then timers as for reliability. Pumps have this bad habit of sometimes not starting after they are turned off and on. The worst failure you can get for a flush system is the open failure because it makes the bed never flood. In hot weather your crops can be dead in a day, or severely stressed.

[Adrena lee]

Yes I like that idea, I saw a guy who had the loop siphon on his system.It was kind of small like mine but he had it going for a few months and was running great. Thanks

Tom Barnhardt said:

You might also want to look at a loop siphon with a timer. This is what I am using in my test system and no problems yet.