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

[gregzz4]

I am looking for input from seasoned users who have either check valves or drilled return lines.

I have read, and read, and read, for 5 months online. I've seen horror stories about check valves failing. I've also seen the same said about drilled holes due to snails and such.

I have flow-tested my system, and am happy with it so far, but would like the option of placing my 3/4" loc-line nozzles either below the surface or just skimming.

[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

[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.

[Cal_stir]

I drilled 2 small holes just below the waterline on each of my locklines, have had no probs for over 2 years, cleaned them @ a month ago and all holes were still flowing.