plumber_bob said:
I know that Saltwater City carries a hang on overflow made by CPR, which would help with your problems. Great little overflow box for a glass tank. I use two on my 125.
I also use the CPR overflow for my glass tank, and for the most part I like it a great deal. There are a few things to keep in mind when using one, though.
1.) You need an Aqualifter or a pump with a powerful enough venturi to draw out any air that gets trapped in the siphon. While this might sound like a pain to anyone who's never used a hang-on overflow, anyone who
has knows that this is a nice feature, and will keep the overflow from ever breaking the siphon.
2.) Make sure that the airline hose used to draw air out of the siphon stays clear of detritus, otherwise it will cease to work. Black airline tubing is best, the clear grows corraline eventually and gets plugged. I know this is painfully obvious to many people on this forum, but if someone had pointed it out to me when I first bought mine it would have saved me a little grief (no disaster, just stress).
3.) While I think the CPR is the best hang-on overflow I've ever used, I think that the design sucks as far as cleaning goes. After a couple of years, you may get sponges, tunicates, and other stuff living in the c-siphon. When enough of these start growing it will drastically reduce the amount of water that can flow through the overflow, and can result in an overflowing tank. The CPR overflow simply cannot be cleaned without removing it from service for a good length of time. If anyone knows a way to do so, please tell me. I just had to buy a second overflow because of this problem, I simply could not shut off my tank for that long.
The CPR aint cheap, but it's not too bad either. I've used cheap ones before and will never go back.
Darrell, where are you located? Maybe someone can recommend a particular person or LFS in your area who will give you good advice on how to hook this up on your particular system.
And yes, I agree with the statement that sumps are the way to go. You can have good success without one, but you will probably achieve better results and have more options with one. DIY sumps are very easy and flexible, without costing a lot. You will be very glad you did it.
Good luck to you.