Backyard Aquaponics
A place to discuss aquaponics

So I am planning on setting up an aquaponic NFT system via pvc over a pre-exisiting aquarium. I have tropical fish that like warmer waters (current temperature is 78F (25.5 C)). Unfortunately I can only lower down to 75F (23.8C) at the lowest and still be in acceptable ranges for the fish. Since the system is being set up to absorb the excess nutrients of this fish, remove it defeats the purpose..
I've read lettuce prefers water temps(?) in very low 70s (20-22C) at the most, and it tends to go to seed in the 80sF (26.6+C)... but I couldn't find anything specific for my water temperature (78F (25.5 C))?? I don't know that it makes a difference for this question but room/air temp is between 65-70F (18.3-21.1C).
I am also trying some herbs but wanted to do lettuce as the veggie in my system.. if it will work..

Any links to studies, or shared experiences, etc would be very helpful. Thank you!

I have read that optimum water temp is 20c to 24c,the lettuce with its roots within this range will take a higher ambient air temp without bolting,my water temp as luck would have it stays between 22c and 24c,tunnel temp reaches 32c with no problems.
I have selected varieties of lettuce that are slow bolting to help as well,Green Oak and Grand Rapids these seem very reliable locally,i do find Grand Rapids slow to germinate and some times maybe only 75% germination, where green oak scores at 95% +

makes a difference what type of lettuce you choose and which varieties. There's a pretty good list of slow bolt and heat resistant varieties on this page -
http://www.gardenbetty.com/2011/07/lettuce-even-in-summer/

Romaine lettuces worked well for me last Summer.

This might give you some useful information - http://www.vegetablegardener.com/item/5044/why-lettuce-bolts-and-what-you-can-do-about-it

and finally this may help - https://www.southernexposure.com/lettuce-ezp-61.html

Thank you both the the information and links I will look into it further.

I have Valerie and Black Seeded Simpsons type lettuce seeds (husband choose them before I knew about temp sensitivity).
Will read into the provided links and hope to find some good "ah ha"s from it, might change out seed types if needed.