Another pump thread, need some help

Sorry for creating another thread about pumps, but my searches have brought up a lot of conversation that doesn't apply to my setup. I'm hoping someone can give me some insight here.

I just received a 29gl Biocube with a DIY acrylic fuge (image below). There is a standpipe in the filter chamber that leaves through a bulkhead in the back of the tank, the overflow line is 3/4". The return line form the fuge is 1/2". Total head is about 3 to 3.2' according to the RC head loss calc with all elbows etc taken into consideration (with the exception of a few pump options that change it to ~5'). The prior owner had this PH3 powerhead for lift, the thing is nasty loud and seems to be just reaching the top of the tank. It works but clearly needs to be replaced, IMO. this is my first overflow/ sump/ fuge so I don't have the experience to know what to buy. It took me half a day just to get it running and understand the process.

The problem is that he made the pump chamber in the fuge ~2" wide. As far as research concludes, nothing more than a Maxi-jet 1200 will fit as a submersible. I already know a MJ400 won't lift through the return, I tried. After reading that most folks have 500gph going through their fuge (is that the advertised pump rating or the actual rate after head loss?), I'm afraid an MJ1200 won't cut it either, or might chatter under pressure the way this current ph is.

If I have to, I'll run an external. If I have to reduce flow I will T off a gate valve back into the fuge.

My question are simply, what pump would you suggest, a mag5 or quiet one 3000 maybe? Or maybe even the Maxi jet 1200, I've read some folks have used them for return, slower flow might suggest longer contact between macros and nitrogens, but I don't want to waste money on inferior equipment, nor do I want to overdo it. I just don't know how fast water can fall through the overflow pipe. Hopefully someone has a similar setup and can help shorten this shopping extravaganza.

Thanks in advance -J

 

Cut the baffels out, move them, or put a pump in the middle chamber where it will fit. You gotta be creative with it and make it work!

 

Thanks, I'm sure I will have to do some work here if I decide to stay with a submersible.

How much flow would you suggest?