What size Mag pump for draining?

[goblin072]

I have 3 tanks at home that I want to drain via pump.

I use to drain into 5 gallon bucket and dump it. I purchased a python clone syphon which allows me to drain and fill my cichlid tanks without buckets. The syphon works off a venturi effect. It hooks to the faucet and can be set to either suck or fill mode.
My sink is higher than the tank so its sucking water up maybe 2 feet. The flow is not that fast for all the water you have to waste for the venturi effect.

I decided that a small electric pump with be better. I don't want to go too strong as it probably will collapse the clear 1/2" tubing.

Which Mag pump with be good? I want to get the #12 (1200gph) so I could use it for mixing too. I think it might be too strong.

I was thinking I could buy some (Drinking water safe) garden hose at home depot. It was 11.00 per 25feet. That would give me better flow for a larger pump and probably would not collapse as easy as the clear tubing does.

Would the garden hose better?
Which Mag?

Thanks!

[NaClFinatic]

I would definitely go smaller. I wouldn't even use my Mag7 to empty into a 5 gallon bucket. I use a Maxijet1200 with 3/8" tubing and fill a 5 gallon bucket in about a minute. A little faster would be nice but it doesn't come shooting out with some tremendous force and I have plenty of time to stop it before overfilling.

How big is your mixing container? I had a mag 7 in a 30 gallon trashcan and that was plenty of current to mix.

Though I did once use my mag 7 to originally fill my tank from the trashcan. And going up 5.5' through 3/8" tubing, it didn't have too much force. But the tube was also loosely held in to the pump outlet so there was some loss of pressure there and it still emptied the can relatively quickly.

[Phurst]

Yeah, I'm thinking that pump is way too big. I just let gravity siphon for me. Using 3/8" I can siphon 5 gallons out in maybe 90 seconds with no pump at all.

[goblin072]

I will be mixing in a 44 gallon Brute trashcan. I spoke with someone that uses a mag 12 for mixing. He likes it because it heats up the water which helps the salt dissolve faster.

I agree that using gravity to drain is pretty fast. I think the venturi was actually a little slower than gravity.

For my freshwater I will be using gravity and fill directly from my sink into the tanks.
I just use Prime in the tank as I am filling it. I hated dumping the 5 gallon buckets.

For salt I want to mix with a MAG and also pump into the tank via mag. I think gravity drain should be ok for water changes.

Its all done with the goal of never have to walk around carrying/spilling 5 gallon buckets again.

The most I do for a water change is around 30 gallons. If I fill into the sump I thought I would have to have a high flow to keep up with the tank pumps. If I leave the pumps off then I run the risk of overflowing the sump.

Why not run the hose and fill from the top of the tank?

One problem is the top is about 7 feet off the ground. A MAG 7 might not be able to handle it or would it? I have been reading that many of the pumps only do about 1/2 the rating. So a 1200gph pump really is closer to 600gph when tested.

I need the real flow at 6 feet to be at least 300gph or 5 gallons per minute.

Maybe MAg 9.5?

[NaClFinatic]

I used a 32 gallon trashcan with a mag 7. The water got hot. Maybe 90 degrees or more with the lid on. I saw a lot of mineral deposits after a month or two. Someone said that can happen faster with warm water and that they mix water at room temp. So I am trying that now. It definitely evaporates less. Its nice that room temp is 70-75 now. If I continue this method I may put a heater in the winter to keep it at least around 70.

FYI - I did get a slow leak in the trashcan so I now use a 37g tank to mix. If I used a trashcan again I would stack two for insurance. I do that for my topoff and put a bag in between them so not likely to get any more leaks.

Any pump will have significant head loss at 7 feet. You can find charts to see what the actual gph is at any height. I think the mag pumps have them on the box and marinedepot.com might have them online also. I am guessing this is based on using the same diameter tubing as the output?

[goblin072]

Thanks for the heads up on the temps.

The person I spoke to said the Brute (Rubbermaid) will not leach chemicals and is better than most trashcans for leaks. He has 4 and non (knock on wood) have leaked. I plan on getting the dolly wheel kit for it so I can move it around.

I think I will get the MAG 9.5 and see how it does for filling at 6 feet.