Something new from GHL...what could it be?

[Mortie31]

I still think that it is correct to claim "continues run" in this context, even when the pump head has "only" a lifetime of 800h.
"Continues" means here that it is allowed to run the pump/motor without a pause without risking to damage through overheating (leave the 800h as limiting factor aside here). Many dosing pumps have a max. duty cycle, e.g. 15 minutes on, 15 minutes off.
800h = 48000 min -> 16800 liters (4400gal) is a lot for a dosing pump. We are not talking about a return pump here.

Price point for the replacement pump head: $29.90

I think the misunderstanding is arising from runnng without a pause, and continuously. if people do this it will only run for a month, before the head "wears". if someone was to use it as you suggested in your literature for a CaRx, how long would you expect it to last "running continuously" ? A month... not good enough I'm afraid.

 

[billwill]

I think the misunderstanding is arising from runnng without a pause, and continuously. if people do this it will only run for a month, before the head "wears". if someone was to use it as you suggested in your literature for a CaRx, how long would you expect it to last "running continuously" ? A month... not good enough I'm afraid.

I agree. I’m glad I found this post. Making a claim of continuous duty for calrx duty is a big deal, and something many reefers have been searching for in an affordable design. Until this claim, it was used masterflex or cole parmer pumps that people bought. I was reading the claims believing this new product could do what those could, but it doesn’t sound like that’s true. A monthly $30 pump head replacement is definitely not acceptable wear and tear for me.

 

[Matthias Gross]

OK, I think you understood what me mean. We mean: It is not necesary to stop operating every few minutes to prevent overheating as it is with many other peristaltic pumps.

Please make a suggestion how we should put it, we are glad to change the description on our web site if we can avoid this kind of discussions.

BTW - why would you use a precise doser for $300 if you just need a permanent flow for you reactor ??? Better buy a cheap return pump for a few $.

 

[Matthias Gross]

This discussion goes entirely the wrong direction. Again. This is a dosing pump, not a return pump.
However, you can use the GHL Doser Maxi for water changes. For approx. 16000 liters. Example 500 l tank. 10% AWC per week. 320 weeks water changes. 6 years water changes.
You can change the 10% (50l) at once. No pause during these 50l necessary (= continous running).

 

[chema]

Indeed, the discussion is going nowhere. This pump is not designed to feed a calrx. Period.

However, Matthias doesn't seem to understand that one of the best ways, if not the best, to feed a calrx is to use a peristaltic pump with variable flow able to work in a permanent way. The original description of this doser seemed to fulfil the requirements, but it is not the case.

 

[Matthias Gross]

Maybe this discussion is good at the end.

I absolutely understand that it has advantages to use a peristaltic pump for calrx when you want a precise flow, although I think that in many cases a normal pump is much cheaper and the way to go.

We have the problem with the lifetime of the pump head of a PP. As you know we have all these moving parts, rollers moving over a tube, tube is "squeezed" thousand times per hour.
We have to rely on the data the pump head vendor gives us. He says 800h - but at full speed.
I can't imagine that other PP have a longer lifetime (at comparable speed/flow/size), they have all the same working principle.

My thought is now: Lifetime will be longer when speed is reduced. I don't know if there is a 1:1 relation between speed and lifetime, it is possible.

So the question is: How much flow per minute would you usually need for calrx?

Give me your feedback, the more opinions the better - we think about the calrx problem. I have a "ultra slow motion" mode in mind. Maybe this helps to solve this issue.

 

[BigJohnny]

I think everyone is right here lol. Technically this pump can run a calcium reactor, just like a Neptune dos can, however both require sacrifices and more frequent replacement parts than a Cole palmer masterflex, which is $1000-$2500 pump NEW. It's not a fair comparison. Now, a used cole parmer can be had for a similar price as this pump, but that's not an apples to apples comparison.

I agree that "continuous use" can be confusing due to the need to replace parts from wear n tear regardless, but masterflex are the same way. Sure, the parts last a lot longer, but that's why it's more expensive.

I'm sure if GHL wanted to come out with a pump to compete with the masterflex they could, and it sure as hell would look cooler , but it would also be much more expensive.

 

[chema]

Maybe this discussion is good at the end.

I absolutely understand that it has advantages to use a peristaltic pump for calrx when you want a precise flow, although I think that in many cases a normal pump is much cheaper and the way to go.

We have the problem with the lifetime of the pump head of a PP. As you know we have all these moving parts, rollers moving over a tube, tube is "squeezed" thousand times per hour.
We have to rely on the data the pump head vendor gives us. He says 800h - but at full speed.
I can't imagine that other PP have a longer lifetime (at comparable speed/flow/size), they have all the same working principle.

My thought is now: Lifetime will be longer when speed is reduced. I don't know if there is a 1:1 relation between speed and lifetime, it is possible.

So the question is: How much flow per minute would you usually need for calrx?

Give me your feedback, the more opinions the better - we think about the calrx problem. I have a "ultra slow motion" mode in mind. Maybe this helps to solve this issue.

Hi Matthias, sorry if my response sounded blunt. It wasn't my intention. You are right about the importance of the flow rate. I have run calcium reactors with around 80-100 ml/h flow, provided by a combination of two peristaltic pumps working alternately (to avoid the permanent use problems).

Truly, providing the right amount of flow to a calcium reactor is a holy grial. You need a peristaltic pump designed to work in a continuous way, with variable flow, strong enough to create some pressure inside the reactor and silent. It doesn't come to a surprise that it may not be cheap.

 

[Ditto]

Have these begun to ship?

 

[Steven Rish]

I have a mixing station 150’ away from my tank. Will this pump push 25’ up 150’ across and 10’ down? Also would I need a siphon break?

 

[Steve1500]

Yes, you can connect a Slave Maxi doser to your KHD/D2.1 combo.

Hi Vinny, I have the 2.1 doser. Can I use it to do Auto water changes? It will need to remove and replace 2G per day. The vertical distance is about 7 ft. And the horizontal travel distance is about 40 ft. I don't have the money for the maxi right now.

Too much for the 2.1?

 

[Vinny@GHLUSA Verified Sponsor]

Hi Vinny, I have the 2.1 doser. Can I use it to do Auto water changes? It will need to remove and replace 2G per day. The vertical distance is about 7 ft. And the horizontal travel distance is about 40 ft. I don't have the money for the maxi right now.

Too much for the 2.1?

The 2.1 motor flow rate is not high enough to do a 2gal WC within the 8 "event" limit.

 

[Auquanut]

@Vinny@GHLUSA Hey Vinny. I've been using the Maxi as a stand alone AWC for almost a year and love it. I've heard it is being discontinued. Is this true? If so, will you still be supporting it for awhile?