Backyard Aquaponics
A place to discuss aquaponics

Hi folks!, I'm in the process of setting up a experimental system.Living in Arizona and with summer approaching I'm a bit concerned about the level of direct sunlight the beds will recieve.Does direct sunlight have a negative effect on bacteria?, I've placed the system where it will receive sun 1/2 the day, morning to mid-afternoon.Thanks all!

Hi brydon2: I live in Florida and have found that a 30% shade cloth has made a big difference. Depending on what you what to grow for the strength of cloth. Check out this site: http://www.protect-o-net.com/guidelines.shtml
When I had the plants in full sun they got burnt during the middle of the summer, I also had more problem with algae before the shade cloth. As far as the bacteria I have no idea, but everything else went better after the cloth.

The bacteria live down in the gravel where they are protected from the direct sunlight. However, in areas with intense sun and hot summers, most of us put up some shade cloth to help the plants out. Once the plants are growing well, they help shade the gravel too and that can keep it a little cooler.

It is important to note that the grow beds in AP will have a strong influence on water temperature.

I'm using 40% shade cloth but I probably could have gone with 50%. I have my fish tanks strongly shaded with heavy fabric so they don't get much sun which has saved me from algae blooms.

Excellent!, I think I'm getting the idea. I suppose plastic sheeting could be used as an affordable alternative? I'm still concerned about water temp with such a small quantity (40 gal), maybe I'll place the tank in the ground, not sure yet.If I start with 30 1" goldfish I will add another tank when they double in size along with a duplicate gravel bed, I think.

Thanks much for the advice

Starting small is good for learning but you will want to keep an eye on temperatures in the water as we head into summer.
Shade cloth can be pretty cheap at the big box stores. $1.75 a running foot for 6' wide for 75% stuff in sand, green or black. a 15 foot roll is under $25 here. Makes pretty good filter material too.

Sounds like your system will be pretty small so you won't need a huge amount.

I will have to check this out at wallyworld , thanks TC !

Which makes me wonder... has anyone ever tried mulching the top of their GBs to keep down temperature and reduce evap? The tops never get wet, so it shouldn't be much of a problem.

Yes I used some pea hay to cover the tops of mine when I first started. Pea hay, 'cause we used to grow it but any hay or straw should be ok. I was concerned at first, but had no detrimental effect. We were getting 40 deg C day temps and my FT water was getting up to 32 deg C. Reflected heat off the ground to the underside of the GB maybe another place for temperature to transfer. Maybe mulch under the GB's too.

This definitely kept the temp's down a bit, and saved a few young plants from snuffin' it, until I got my shade house cover over.

I thought about doing it but never have. Around here I would probably use spanish moss, oak leaves or wood chips. Only drawback I really see with mulch on top of the gravel is trying not to get too much of it burried down into the gravel when re-planting and harvesting and such.

Keep in mind that if you mulch over the grow beds, you want to choose something that will still breath well so the bacteria in the grow beds can get plenty of air. And you want to choose stuff that won't leach negative stuff into your fish water if you do get a heavy rain.