CPR Overflow or U-tube

[cpllongjk]

Im having a dilema; choosing cpr overflow which requires a pump to maintain the siphon, or u-tube which doesnt.

Also, i only need 300-500gph max. not a lot. I also only have 1.5" of space inside tank for the pre-filter box. Which makes cpr look tempting.

I love lifereef overflows, but they are a bit on the expensive side. And if i could drill this tank i would, but i cant. So that is why hob overflow is a must. Help me out, im trying to get this finished by next week. I custom built the sump in my stand, just waiting on the overflow to switch over to 15g more water volume.

my tank is 24g aquapod, so youll understand why the space restrictions.

 

[Eskie]

Both have the risk of losing siphon resulting in flooding, although the CPR with pump is less likely to do that by avoiding trapped air. The U tubes can work, but are more prone to failure. While the CPR is more expensive than 2 U tubes, I would use it for the peace of mind (which is still not 100% with any external overflow.

Is there any reason you don't want to drill the rear wall instead? It's cheaper and reliable.

 

[victor_c3]

I purchased a CPR siphon box for my 30 gallon tank (I bought the CS90 if I remember right) and so far I haven't had any major issues with it yet. It made a fair ammount of gurgling for the first 1-3 days of use, but it has since gone away.

As far as losing siphon goes, I don't see how the box could work without a pump. As long as you have the pump and the pump is working alright, then there shouldn't be any issues with the siphon starting back up after a power outage. I've experimented and dealt with a few power outages and the siphon box has never failed to restart.

The box is much larger in person than I thought it would be - especially the back side of the box. Fortunately it is clear and, with my black background, isn't too much of an eyesore. But this would probably apply to any other overflows on the market as well.

I have no major complaints with the CPR box and I probably would purchase one again. However I'm definately going to get a drilled tank for my next aquarium.