hello Richie here looking for advice on a scrubber..

I'll have to look at the pump tomorrow, but after your head loss it might be enough, you need at least 200GPH through the scrubber

 

This might answer a few of your questions

https://www.turbosaquatics.com/threads/turbo-algae-scrubber-faqs.18/

 

What is your measurement from the top of your sump to the underside of your stand?

 

You barely have room, you would be able to get the screen out, but it would be difficult. In your situation, it would be better to remove the unit with each cleaning. I had this scenario in mind when I designed the shelf bracket system. Having something like this would allow you to tilt or "roll" the unit so you could remove it without having to disconnect/reconnect the plumbing in the sump area each time.

As far as a return policy, I've ran across this situation once before and had to give a refund because I didn't preface the sale with "make sure it fits". So I would say that the first step here is to create a mock-up out of cardboard or posterboard and tape and see if you can make it work. The dims I posted include the heat sinks, and with those installed it's not a perfect cube shaped box, but I think the diagonal dimension of the acrylic main body is about 9.25", which is the clearance you would need to 'roll' it. Keep in mind that you have to account for your shelf also. But, your shelf or stand can also be a box made out of PVC pipe that is free-standing in the sump like this:



^^ that's an old L2 BTW

 

Draw down on power outage should be a simple thing. The water is going to drain down to the point where your overflow fence is minimum (like the bottom edge of the teeth on the overflow box) or to the lowest level that your return plumbing sits. Water will always drain through your overflow to the low point, to get lower than that, your return plumbing is the only way it can get lower, via backsiphoning.

I don't know how to explain the difference in water level fluctuation you are seeing, unless you are using a check valve and it is not working right 100% of the time. A check valve should only be used to control the backsiphoning rate in order to prevent a return pump from failing to start properly, it should not be used to prevent backsiphoning from overflowing the sump - sump sizing, operating water level management, and return line position should be arranged to prohibit that scenario.

The light fixtures are NOT waterproof. So you have to figure out what is going on with your drainage per the above statements, and determine your maximum power-off water level, and make sure your scrubber does not get mounted below that position.

Other factors at play are your ATO and sensors. This is an additional factor that I always figure into the "worst case scenario". Say your ATO is 5 gallons. Say you just fill the bucket, and you have an "operating" level line marked in your sump. Right after you fill the bucket, your ATO sensor fails and the ATO pump dumps the full 5 gallons into your tank. Right after that, your power fails and your sump fills to the max. The scrubber must be above this line. Let me repeat that. MUST. Under no circumstances or scenarios can the water level rise above the bottom of the scrubber base.

 

Can't see that link because I'm not a member...and registration is disabled. Looks like their forum is closed due to spammers. Boy is that a simple fix though, hmm.

Right click and save, upload here

 

I think I know what you are trying to describe, return line siphon breaks can get clogged so you need to make sure they stay clear, that might be the issue.

 

I would say that they are not long-term verified and tested. They might work, or might not. But they are being touted as if they have been. That's the issue, IMO. The floating type scrubbers perform differently, and it has been assumed/purported that things are apples-to-apples and it may not be

 

So does the text above match up with the photo? I'm a bit confused. Is the black 90 on the right the return line?

 

Sorry, I'm totally lost with your explanation.