Appropriateness of Iwaki Magnetic Pump?

[RobertN]

Hi All--
I saw a used Iwaki Magnetic Pump, MD-100RLT. It looked in really good shape and was a good price. I am planning, in the next few months, to upgrade my 100g cube t0 a 180g peninsula tank. I will need a stronger/better pump than I am currently using, so when I saw this, I thought it might be a great opportunity. However, if it is oversized even for a 180g tank, then naturally I don't want to get it. What do you folks out there who know more than I about such things think about the appropriateness of that pump with a 180g tank?

Thanks in advance!
Robert

 

[Muttley000]

How much head pressure do you expect? Running anything else off it? At 4' head it delivers 2000 GPH. Not too much IMO as you could dial it down a ways. I have a pair of 55 size of the same pump and love them!

 

[rockskimmerflow]

Hi All--
I saw a used Iwaki Magnetic Pump, MD-100RLT. It looked in really good shape and was a good price. I am planning, in the next few months, to upgrade my 100g cube t0 a 180g peninsula tank. I will need a stronger/better pump than I am currently using, so when I saw this, I thought it might be a great opportunity. However, if it is oversized even for a 180g tank, then naturally I don't want to get it. What do you folks out there who know more than I about such things think about the appropriateness of that pump with a 180g tank?

Thanks in advance!
Robert

Its really oversized unless you plan to use eductors on all your return outlets and use its pressure capabilities to full advantage, eliminating any need for powerheads. Otherwise an md40rxt is the best flow option from the iwaki line for your system. Id recommend a fluval sp4 or sp6 if you want a quieter, less power hungry flow solution with a stout reliability repuation. Not quite as robust as the iwaki, but then again nothing else really is. The fluval would be my first choice for a 180g return at low head heights.

 

[HawaiianReef]

Yup, that 100 is a lot of pump for a 180.
Just some FYI. The A/C pumps, or external only pumps are great reliable powerhouses. They are going to draw more power than say a D/C china pump like the Jabao sinewave pumps and the A/C pumps are Not variable. They operate at one speed (unless you use a VFD). But they deliver better volume of water at higher and longer distances. D/C pumps can often lose 2/3 there rated gph at just 5 feet.
Also, A/C motors ARE rebuildable. The only parts to change are the motor bearings. That MD40rxt would cost you about 15 dollars for some high quality Japan made bearings and those would last 10+ years easily. Thats the motor side. The pump side is also easily maintained. Every part is available, but they never wear. The impeller spins in a ceramic bearing that is submerged because its the wet side of the pump. Just change the O ring if you like.
Your in the right direction IMO. A 180 tank means you probably are here to stay for a while. The A/C pumps are the only way to go for that. Let the return pump draw a bit more power, and run D/C for circulation and leds for lights to save the electricity.
BTW, this goes for pretty much All A/C external pumps. Blueline and little giants are also very good.
I hope Im not off topic. And sorry for the rambling on..

David

 

[Dr. Dendrostein]

How much head pressure do you expect? Running anything else off it? At 4' head it delivers 2000 GPH. Not too much IMO as you could dial it down a ways. I have a pair of 55 size of the same pump and love them!

With those specs, pump should turn over water 10x in an hour. Correct me if wrong someone

Good brand I'd buy

 

[Muttley000]

With those specs, pump should turn over water 10x in an hour. Correct me if wrong someone

That was my basis for saying it was ok. If the sump was absolutely tiny then you may have a bubble problem

 

[Dr. Dendrostein]

That was my basis for saying it was ok. If the sump was absolutely tiny then you may have a bubble problem

You can always throttle back discharge on pump.
If me and pump is outside of sump, put pump in a dry sump so if it leaks later you can catch, before a headache

 

[DCR]

Unless you have a basement sump, I would chose some other pump with lower head - such as Iwaki 30 RLXT if you like their quality. The 100 is designed for high head applications. It is going to be very inefficient run out on the end of its curve. It is also very loud.

 

[HawaiianReef]

The 100 delivers just 800gph than a 40. The 100 is designed to push water really high and really far.
It would work on the 180, but that 100 also uses 400 watts to do 2100 gph. While the 40 uses just 150 watts and does 1300.
I would put two 40s and get 2600 gph before running one 100 at the typical 4-5' height. That would use less electricity while adding the security of redundancy. But that is still more than needed. One 40 is great.
But like everything else in our hobby, there's always another way to skin a cat.
https://www.bulkreefsupply.com/iwak...7-D-qaTvlkfM8DwADonXEGTrlxgFkYDRoCpNkQAvD_BwE

 

[Blue Spot Octopus]

I have a Iwaki 30 on my 120 gallon tank so for you I think a 40 would work great. Now it your sump is in a basement that is a different story.

 

[HawaiianReef]

If you do end up using a used one, take the time and rebuild it. It's a lot easier than it seems.
Here's a 40rlxt all apart showing the sealed bearing on the armature shaft.
And another of the pump taken apart. This pump was running for over 8 years non-stop.
PM me if you do decide to and need any guidance.

 

[Dr. Dendrostein]

If you do end up using a used one, take the time and rebuild it. It's a lot easier than it seems.
Here's a 40rlxt all apart showing the sealed bearing on the armature shaft.
And another of the pump taken apart. This pump was running for over 8 years non-stop.
PM me if you do decide to and need any guidance.

I want your pump. Tech friendly, that's rare

 

[HawaiianReef]

I started a thread on rebuilding a little giant. Check my profile and started threads. Note I kinda flaked and didnt finish it up yet.;Wacky *But I Will!

 

[ca1ore]

An Iwaki was certainly my longevity champion. Bought in 1988; retired at the end of 2008. I suppose I could have rebuilt it, but I figured it had more than paid for itself. I'd think the model 100 would be way too much pump for a 180, and unecessary if the sump is in the stand. Heck, I'm using a similar panworld pump on my 450 from the basement. AC versus DC makes much less difference than the task the pump is designed to perform. Most DC pumps are designed to give high flow under low pressure applications. The 'efficiency' is something of a shell game.

 

[RobertN]

Wow--thanks folks for all the great feedback and info! Very helpful. It's also what I was afraid of. The pump is going to go in a sump in the stand under the tank, so no basement location. This pump I found looks practically new and I can get it for $125. A new MD40rxt is $300+.
Is there a way to dial it down, as one or two of you suggested above? Or as rockskimmerflow suggested, could I use the extra power from this pump to replace the need for some or all powerheads by routing some of it's flow through eductors placed in 2 or 3 spots? I'm just trying to figure out if there's a way to make this reasonably work well since it is such a reliable, workhorse of a pump and this seems to be such a great deal.

 

[RobertN]

The size of the sump I'm hoping to use would be 75-90g. Can this Iwaki 100rlt be put completely into a wet sump?

 

[Muttley000]

That is a great price in that pump! If these guys talk you out of it I'd be interested! Through educators is a place where this pump shines IMO so definitely that is a good option. You can put a ball valve on the exit side of the pump and turn it down as far as you want, just don't limit the intake. The eductors are going to create back pressure that will cause you to loose some of the GPH, so at just the head from your sump to tank plumbing and height difference you are going to be down to less than 10 times turnover in your tank, and the eductors are going to cause you more loss. You will still need other flow devices in the tank.
I am curious as what the people who say this is way too much pump for this tank shoot for in return pump turn overs through the display. The 8 times I'm guessing you would get with the eductors added, and the ability to turn it down if it was too much, seems far from excessive to me. If there is a different opinion I would like to learn to understand it!
If your last question is can you submerge it the answer is no.

 

[HawaiianReef]

You dont really need to dail it down. It's not that much more flow. Just about 800gph more. You better off getting a 40rlxt. It'll pay for itself quickly with the savings on electricity. You can find them under 200 used.

 

[HawaiianReef]

That is a great price in that pump! If these guys talk you out of it I'd be interested! Through educators is a place where this pump shines IMO so definitely that is a good option. You can put a ball valve on the exit side of the pump and turn it down as far as you want, just don't limit the intake. The eductors are going to create back pressure that will cause you to loose some of the GPH, so at just the head from your sump to tank plumbing and height difference you are going to be down to less than 10 times turnover in your tank, and the eductors are going to cause you more loss. You will still need other flow devices in the tank.
I am curious as what the people who say this is way too much pump for this tank shoot for in return pump turn overs through the display. The 8 times I'm guessing you would get with the eductors added, and the ability to turn it down if it was too much, seems far from excessive to me. If there is a different opinion I would like to learn to understand it!
If your last question is can you submerge it the answer is no.

It's not so much the flow of this pump, but the power consumption. You wind up getting 1/3 more flow at 3 times more wattage.
Once you get into the bigger tanks, the yearly cost of electricity adds up pretty quickly.

 

[ca1ore]

I am curious as what the people who say this is way too much pump for this tank shoot for in return pump turn overs through the display.

3-4x actual display volume. A nominal 180 is closer to 160 actual gallons (before rock displacement). I do 1,550 from my PanWorld 250 for 400 gallons of display volume.