Sump questions

rennne39

Member
This is my first time having a sump and I am trying to figure out how do I know how much water to fill the sump up with
 
What kind of overflow you using? Fill it slowly and leave room just in case of power outage. Use Floats either optical or manual with controller. High Float, Low Float at least I have 5 in total plus leak sensors. Hope this helps
 
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What kind of overflow you using? Fill it slowly and leave room just in case of power outage. Use Floats either optical or manual with controller. High Float, Low Float at least I have 4 in total plus leak sensors. Hope this helps
Can you explain floats
 
With a sump overflow is key; is this a drilled tank or HOB Overflow?

HOB Overflows have a tendency to fail just a note

Floats are of course optional. You will need a controller though which I use Apex with the FMM module

Example I have 5 Floats in my system all optical

Optical are best but you can do manual floats as well

High Float -- tells me something is wrong either my ato is stuck or something else and alarms me

Low Float -- triggers my ato to turn on -- my ato also has max time it goes on so it dont overflow my sump

Return Float -- triggers my return pump off which either my ato is too low

Emergency Float which is where my overflow is If tank water goes over a certain area triggers an alarm an shuts off my pumps.

I also have an Ato float in my Ato reservoir to tell me my reservoir needs to be refilled and not to turn on my pump if its too low.

Again all this is done through controller.

This is optical float Apex
https://www.bulkreefsupply.com/os-1...a-mNzspKMsGmJVjTdU0ub_K-OeztZgBBoC8IIQAvD_BwE

Manual float which you can do with a breakout Box Apex for example

https://www.ebay.com/itm/Top-Mini-T...064706?hash=item261ef400c2:g:7SoAAOSwNpNa4uKp

I also recommend leak sensors never can you be to careful. You're dealing with lots of water and if not careful will get a water damage. Especially if you're using a HOB overflow
 
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You have 2 situations to worry about:
1. your overflow into your sump gets plugged, causing your return pump to send the entire contents of the sump into the tank. Multiple overflows or a return float covers that.
2. your pump shuts off, causing some amount of your tank to drain into your sump. This isn't just from the overflows, but your return line magically turns into a siphon and starts sucking tank water into the sump until it hits an air pocket.

Number 2 is the one you need to work out. You need a siphon break in your return line so that it will stop sucking water soon after the return pump stops. Set it up so that the sump can hold all of the water from the tank that will drain from the overflows and until the siphon break kicks in. Mine drains to about 2 inches below the top of the sump. Use the calculator on the home page to determine how much water should drain and how much volume in the sump is needed for it.

Once you get that right, then you can balance your drains against the return pump so the sump level stays constant and get to a good depth for your skimmer to operate. Then turn the pump off, mark the level in the sump where the water fills to and never fill it higher than that. It sounds involved, but once you get all of that sorted out you rarely need to worry about it again.
 
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