All times are UTC + 8 hours




Post new topic Reply to topic  [ 5 posts ] 
Author Message
PostPosted: Mar 22nd, '17, 08:37 
Offline

Joined: Mar 22nd, '17, 08:18
Posts: 2
Gender: Male
Are you human?: yes
Location: Florida, USA
Hi everyone, newbie here hoping you can help.

I'm starting my first system and think I want to start with a Flood & Drain based on a small 75L/20g tank. From what I have read I want to stay away from the bell siphon for now (it seems like a hassle to set up and I worry I will design it wrong, it will fail to fire and I'll overflow my GB).

My question is this, if I want to go with a Flood & Drain set up on a timer, how do I know how often to have the pump on vs off? Also, I have read I should circulate the full volume of the fish tank within the hour. How can I accomplish this while still allowing some "dry" time in the GB and not leave my fish without any water.

Sorry if this a dumb question. I just haven't been able to find a formula in my research.

Thanks in advance for any help or suggestions you can provide!


Top
 Profile  
Reply with quote  
    Advertisement
 
PostPosted: Mar 22nd, '17, 15:05 
Offline
Moderator
Moderator
User avatar

Joined: Aug 26th, '10, 07:17
Posts: 8575
Gender: Male
Are you human?: YES
Location: Oregon, USA
With only a 20 gallon tank I'd consider running Constant Flood instead of Timed Flood and Drain that way you won't have large fluctuations of the fish tank volume which can stress the fish. The dry time in the grow bed is not as important as having oxygenated water flowing through the system.

How large is the grow bed attached to this tank?


Top
 Profile  
Reply with quote  
PostPosted: Mar 22nd, '17, 16:55 
Offline
A posting God
A posting God
User avatar

Joined: Sep 29th, '14, 13:15
Posts: 2063
Location: Australia
Gender: Male
Are you human?: mostly
Location: Perth, West Aust
agree with scotty above.... plus

(a) have the water level down below the media at least 2-3" if using Constant Flood
(b) use clay balls if you can since they wick moisture into the root zone better than rocks/gravel.
(c) add a ball valve at the bottom of the grow bed and simply drain it out to a bucket once a week.
will help do water changes and also gets rid of some of the excess crud.
and also helps keep good circulation in the grow bed.


if you want timer for other reasons then simply let water stay in grow bed and dont drain.
the continuous/regular flow is really for the fish benefit & system circulation - much less critical for the plants.
If fish are getting enough DO then plants will too.

_________________
.
Darren ( dlf_perth )

May the fish sh*t and the plants grow.....


Top
 Profile  
Reply with quote  
PostPosted: Mar 22nd, '17, 20:38 
Offline

Joined: Mar 22nd, '17, 08:18
Posts: 2
Gender: Male
Are you human?: yes
Location: Florida, USA
Thanks for the responses! I was thinking of having a 20g GB as well. What would be the minimum size you would suggest to do flood and drain?

Some of the crops I want to grow (strawberries and cucumbers) I've read don't do well in Constant flood. I do understand your point though, if I want to start that small I should and will consider constant flood.


Also, I appreciate the extra steps/info! I'll be sure to use clay, add a valve to clean out the bottom and keep the water level below 2"-3"


Top
 Profile  
Reply with quote  
PostPosted: Mar 22nd, '17, 22:35 
Offline
Valued Contributor
Valued Contributor

Joined: Aug 12th, '16, 00:34
Posts: 64
Gender: Male
Are you human?: YES
Location: Mississippi, USA
I have a similar system to the one you're talking about building. I have a 40 gallon FT that I try keep at about 35 gallons. I have a 17 gallon GB and a 17 gallon DWC. I have my system currently running a Flood and Drain where at the start of every hour of the day from 7 am to 9 pm the pump runs for 15 minutes. I had to ball valve and control my water inlet so that within this 15 minutes my system flood and drains twice. Then I have a dry period of 45 minutes and then throughout the night. I have had good luck with my system so far the only problem that has really gotten me is the lighting, which I hope I've taken are of now. You can check the thread "First Indoor AP" if you want a few more details. I just planted a strawberry plant and blueberry bush to experiment. We will see how low I can get my pH without killing my fish.

All that being said I think your sizes will be okay. The above noted steps by perth and scotty will be very helpful to keep in mind as your designing and building.

-Tyler


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC + 8 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

Powered by phpBB® Forum Software © phpBB Group
Portal by phpBB3 Portal © phpBB Türkiye
[ Time : 0.068s | 18 Queries | GZIP : Off ]