Backyard Aquaponics
A place to discuss aquaponics

Was looking at some smaller tomato seedlings getting fried in the sun. Thought maybe they were not getting enough water even tho the system is now on 15 on 15 off. Put my hand on the gravel. darn that's warm. Has anyone looked into the temp of different media. I'm going to cover the GB's later. Does clay heat up the same as gravel.

Mine does, I try to grow higher bushes next to the smaller plants to provide some shade. I also leave the beds flooded when establishing seedlings.

Raise your siphon level when they're small... or planting from seed... flood to the top (just)... then drop it back... or water periodically with a watering can...

What would you say would be optimal temp range for both fish and plants OBO?

oooow, that is totally dependendent on your fish. My plants are doing much better now the weather has warmed up. Plants were very sssslow at 10 deg c water temp, now heading towards 20, and rocketing along.

High water temps can cause some plants to bolt to seed, the same as cold water temps can also.

I reckon anything around 20 deg c + / - 2 deg c works really really well.

Plant in optimum season/time and the GB temps will be right,
try to exceed either and they wont gernimate (or poor germination) or will bolt as OB says

Also, the reason that many of us in hot climates use some shade cloth over the system is to help moderate the scorching hot gravel thing. The top surface of the gravel in the sun can get really hot so having some bigger plants around to shade the seedlings until they establish can be a good thing.

I've noticed that my system temps cooled off a little bit as the sweet potato vines covered the monster bed shading the gravel.

My gravel - which is dark in colour, certainly gets a lot hotter than my clay balls. Once the plants get going though, they tend to shade the media quite effectivelly (as others have indicated).