Dolphin 900 pump

Hello,
I am setting up a new 125 gallon Oceanic tank and was wondering if my LFS sold me the right pump, a Dolphin 900.
It didn't come with a head pressure/ gpm graph, and the web site doesn't show one for this model. It states max flow as 900 gph, 17 ft max (pressure?).
I am plumbing 1 " pvc spa flex and rigid pipe combo, tee'd for discharge back into tank corners (2 lines). Something like 9 ft horizontal pipe with one elbow to get me out of the cabinet and three elbows to get me back into the tank at each corner. I put two 1/2" outlets on each corner discharge (vertically stacked, one about 3" lower than the other). I thought this might help create some flow patterns in such a long tank (6ft).
My husband is begging me to put in two more elbows, to clean up the look of the back of the tank where the hoses leave the tee and arc up to the discharge. I admit that would look and sit better but am worried that this would be problematic with the pump. He thinks I am overanalyzing things, but I am a scientist by trade and I can't help it. Could I do this without trouble? Could I do this with a larger pump? Do I need a larger pump anyway?
Other facts: 20 gallon tall glass aquarium for sump, 2 tidepool SOS overflows ('up to 600 gph each') with 1-1/4" drain hoses, 30 gallon refugium feed by tee off of one drain hose with gravity drain to sump via bulkheads, turbofloter 1000 skimmer
I know you guys have better things to do than analyze my situation, but I need HELP! I already have a $550 store credit at the lfs from all of the wrong stuff that they sold me so far, I want some better advice than what I get there.
PS. I plumbed a tee with a ball valve straight off of the pump return line to direct water back into the sump if necessary (3/4" valve/ pipe). I don't know if I need that but I read about that here and thought better safe than sorry.
Thank you, Thank you, Thank you, for all and any input!!
-Christine :)
 

melbournefl

Member
Well I've tried in vain to find a Dolphin "900" product listing with any of the online sources I use. Are you sure you have the model number right?
Just wondering,
Paul
 
So sorry!
Just when I thought I gave enough details to put someone to sleep, I missed some!
It's a Dolphin - Pond/ Tank Master, Submersible/ In Line, DP-900
I know, there isn't much info out there, I tried.
Still, any input or advice is appreciated.
-Just talked to the lfs. He said it should be fine because the overflows never really flow what they are rated to (mine are 'up to 600 gph x 2 overflow boxes), so I would't want to 'overpump/ overfull'. Is this really true? Still I think that since my pump is rated for max flow of 900 gph, that after all of the fittings and elbows, etc that flow would really be considerably less. Right? Help! My brain hurts.
 

melbournefl

Member
Zafira... I'm sorry but it's getting late for me to be thinking, I promise to look at this more on Friday okay. My gut reaction is that if you go with 90 degree "sweeps" rather than "ells" you'll be avoiding *some* of the head pressure but I really need to think more before I answer :)
sorry but it's late for me, I get up at 4am and just can't think at this time of night (actually according to my wife, I can't really think anytime of day or night or I wouldn't be putting this kind of money into something that could have been a nice sushi meal LOL :eek: )
Paul
 

melbournefl

Member
Okay let's start this with a *semi* fresh mind :) What's the height difference from the pump to the returns inlets? I'm going to guess here and say 3 feet (if I'm too far off let me know) plus 3 90 degree elbows right? I'm going to go out on a limb and make a "guesstimate" that you're probably getting a maximum of 6-700 gallons return. That said, let me make another observation. I don't understand why your LFS has suggested that you buy a pump with that much less capacity than your overflows, you should have a valve installed on the pump return line anyway so you can always "throttle back" on the return if the overflows can't keep up. Personally, I'd "clean up" the installation using 90 degree sweep fittings if that's feasible and upgrade the pump to one with at least 1200 GPH at zero head, you know already that's going to be lowered by the plumbing so your overflows should be able to keep up without any problem.
BTW, what other circulation are you going to have in your tank? i.e. powerheads etc. What are you going to be trying to keep?
With any luck, Broomer, our favorite resident plumber will jump in here and correct me if I'm too far off with this.
Good luck whatever you decide and ENJOY!
Paul
 
Paul,
Thanks for your attention. I called the lfs yesterday and said that I probably needed a bigger pump. The guy waffled a bit on if I should or shouldn't, then decided I shouldn't change my pump, 'cause 900 gph should be plenty. Yes, I said , but wouldn't the flow be alot less than that considering height, elbows, head pressure, etc??
Him: Well, yes, well no, not if you plumb it right. Just let me tell you how to plumb it and you will be fine.
Me: Plumbing it pretty straightforward, just worried about the 1 elbow I needed to get me out of the tank.
Him: You don't need an elbow
Me: I do to get out of the cabinet
Him: Use flex line
Me: I am
Him: Listen bring your pump in to the store and I will get you all set up, this is a mess.
Me: Fine what time will you be available, and the store manager at the same time 'cause we need to resolve thus $550.00 store credit thing
I go when he says (takes me an hour to get there). I wait 1/2 hour 'till he is available. He procedes to laugh at my plumbing, gets distracted about how to 'set up the pump', and rigs a return line for the corner of my tank in 3/4" flex and pvc. 'See, isn't that easy? Now go home and make another one for the otherside, It doesn't need to be this hard' Too bad though, it looks like you did such a nice glue job on your 'submarine part looking set-up'
I told him that this return line is exactly what I had at home in 1" but that doesn't change the whole head pressure/ pump size issue. He says yes it does. What??? Again:
Me: What about the elbow to get out of the cabinet?
Him: You dont need it, use the vinyl flex with hose barbs.
Me: How is that better than spa flex with pvc fittings? Wouldn't it reduce the flow less?
Him: Just do it the way I said, its easier
Me: Doing everything again is actually not easier you see....
Him: Yep, it is you'll see. And bring in your turboflotor next week and I can plumb that for you to.
Me: I already set it up like the directions said.
Him: No, no no. I will do it so you don't have bubbles in your sump
Me: Can you just tell me how?
Him: Nope, just bring it in, I'll do it
I just gave in and said OK. But I left really mad inside. Did he act this way 'cause I am female? I hope not. I'm not going to freak to bad until I get my money back.
I blew my whole night trying to get this right and all I get is some macho guy telling me it is easier for him to do it for me than tell me, and then show me something else that I already had. Oh yeah, and the manager that was supossed to be there to refund my $$ wasn't, I have been trying to get ahold of him for 3 weeks!!!
Thank god it's friday!
Help me saltwaterfish.com community, you are my only hope!
PS.-- Anyone out their placed a submersible pump on its end in the sump? Like suction-cupping it to the wall, with the intake at sump floor? It was a suggestion to me.
 

melbournefl

Member
LOL Christine, makes you wonder doesn't it? I too hope he's not being a smart-ass cuz you're a woman but ... maybe you should try taking your husband in on the next trip and see if the attitude is any different :eek:
I read through what he said and he's kinda' right with the flex hose and barb fittings being less head then 90 degree fittings but, why re-plumb the setup when all you're really asking is to exchange the 900 for a more powerful pump? My earlier thoughts were based on not redoing everything, there are several methods to reduce the head pressure if you're willing to start over of course. Bottom line is, the maximum you're going to get out of that pump is 900 GPH, no matter how you plumb it. If you want more circulation you only have two options, bigger pump or powerheads. I personally don't like looking at powerheads but that's just my opinion and I'm sure many will dispute that LOL Since you're starting from scratch, why not get the tank the way YOU want it?
Regarding the pump's placement I'm going to withhold comment since I've no submersibles in my setup. I chose externals to avoid the potential heat transfer.
When you decide how you want to pursue this, let the board know and I'm sure you'll get lot's of suggestions if you need them.
Good luck!
Paul
 
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