Opinions appreciated: check valve vs anti-siphon holes in overflow returns

[ensquire]

I guess that there is danger either way. Blockages being the prime concern.
Personally, locline just below the surface is my choice.

[gregzz4]

Originally Posted by ensquire

I guess that there is danger either way. Blockages being the prime concern.
Personally, locline just below the surface is my choice.

No offence, but you're not giving me a long-time user experience with your reply.
I'm looking for user responses with long-time experience.

[gregzz4]

Should I use a union check valve or not?
I don't want to drill my lines.
What's your experience?

[Aquattro]

I've been using a check valve for a year and a half, no issues.

[Doug]

Originally Posted by gregzz4

Should I use a union check valve or not?
I don't want to drill my lines.
What's your experience?

Whats the matter with his response?

I have done my tanks that way for 40yrs. Never have I ever used a check valve. My returns have just been under the surface, with the sump holding any back flow.

I also drilled a 1/8th. in. hole for back up but as mentioned, my systems would be fine without.

I liked to drill them om an upwards angle so the water sprayed straight down. Also on the backside, where the piping came over the top. I found snails could not bother it as much when between the pipe and the glass with not much room.

Only snail problem I have had was one the cover the hole partially and the water squirted in the air. That was corrected by the above angle and placement of the holes.

Having the return just below the water line is still the best solution as was said. If its under far enough that back flow will flood the sump, {for whatever reason I,m not sure},then a check valve is the only solution. Although many have run them with great success, I have read many stories of floods from their failure.

[fishytime]

most check valve failures are due to the seals getting schmengy....I always recommend that people buy two and swap them out for cleaning......that and make sure that your sump can handle any back siphoning that may happen in a "worse case" scenario

[Doug]

Originally Posted by fishytime

most check valve failures are due to the seals getting schmengy....I always recommend that people buy two and swap them out for cleaning......that and make sure that your sump can handle any back siphoning that may happen in a "worse case" scenario

Good advice.

[Delphinus]

I've run both anti siphon holes and check valves on tanks in the past. Both are methods equally prone to failure and there will always be a chance they fail one time when you're unprepared. Maintenance will reduce the risk but not eliminate it completely.

I prefer the KISS principle.. On my tanks I run now I keep enough space in my sump to handle the backflow. The higher the output nozzles the less backflow volume you need to account for. Plus, having output nozzles near the surface has the added advantage keeps better surface agitation.

[paddyob]

Originally Posted by gregzz4

No offence, but you're not giving me a long-time user experience with your reply.
I'm looking for user responses with long-time experience.

How do you know how long this person has been in fish keeping.

I guess I won't offer advice.

[reefme]

Just removed the union check valve yesterday and run the nozzle just below water surface. Reason for removing is every time I turn off and on the pump it making stupid noise.