quietest return pump

[sphelps]

Originally Posted by Canadian

Obviously there are different schools of though on this but I don't see the point in running a return pump at a rate greater than what your skimmer can accommodate. It would be a complete waste of hydro. I'd run the smallest return pump you can to meet your head loss needs to keep up with your skimmer and only use propeller pumps for flow in the display and even one in the sump to keep detritus from collecting.

A good point but I see more to a sump than a skimmer. A higher return increases tank flow and reduces the demand for supplemental in tank flow, a big plus in my books. Also more flow increases surface tension and reduces scum build up in the display, it will also keep things suspended longer and filter more out of the display sending it to the sump quicker. Sumps can also hold mechanical filtration like socks and floss and chemical like carbon. These can benefit from higher flow. Finally things like heaters and pumps will work better with an increased convective heat transfer effect.

You don't have to run high flow but there are certainly benefits to it.

[Parker]

Originally Posted by Canadian

Obviously there are different schools of though on this but I don't see the point in running a return pump at a rate greater than what your skimmer can accommodate. It would be a complete waste of hydro. I'd run the smallest return pump you can to meet your head loss needs to keep up with your skimmer and only use propeller pumps for flow in the display and even one in the sump to keep detritus from collecting.

Originally Posted by sphelps

A good point but I see more to a sump than a skimmer. A higher return increases tank flow and reduces the demand for supplemental in tank flow, a big plus in my books. Also more flow increases surface tension and reduces scum build up in the display, it will also keep things suspended longer and filter more out of the display sending it to the sump quicker. Sumps can also hold mechanical filtration like socks and floss and chemical like carbon. These can benefit from higher flow. Finally things like heaters and pumps will work better with an increased convective heat transfer effect.

You don't have to run high flow but there are certainly benefits to it.

My number one reason for running a large return pump is I have enough flow from one pump to drive my entire mechanical system sans skimmer from one pump. My dart supplies my carbon and phosphate reactors, calc reactor, UV filter, fuge and tank return. Also, if your running your skimmer passively in your sump ( your return isn't plumbed directly into the skimmer ) your not skimming the entire contents of water flowing through that chamber, I don't think how fast or slow the water is flowing past the skimmer makes much of a difference. The skimmer still processes the same amount of water.

My second reason for running two additional darts is astetics. If I can avoid seeing mechanical devices in my display tank it's worth the extra noise, electrical costs and plumbing cost to me. As you mentioned people have different schools of thought.

[lastlight]

Yeah it's a RD2000 and is a skimmer pump.

I was under the impression the pumps were practically noiseless and myself and others have been suprised to find this isn't always the case. The issues I've read about may have primarily been skimmer pumps I can't recall. But the userbase is super small and I've personally read of enough issues in the forum to question the over-hyped quality (imo) of their pumps.

[sphelps]

Originally Posted by lastlight

Yeah it's a RD2000 and is a skimmer pump.

I was under the impression the pumps were practically noiseless and myself and others have been suprised to find this isn't always the case. The issues I've read about may have primarily been skimmer pumps I can't recall. But the userbase is super small and I've personally read of enough issues in the forum to question the over-hyped quality (imo) of their pumps.

Skimmers are a funny thing, honestly no matter what type of skimmer you have you will have issues with it. This is because skimmer performance is based on so many variables we can't even begin to explain them. For example if I put my hand in my tank for a just a couple seconds my skimmer will stop working properly for a few minutes, and that's just one example. I use to build custom skimmers which replicated BKs but I soon quit because of the issues I had to deal with. I use to test the crap out of them and they would work just fine but as soon as the customer would get it, nothing but problems. I also run a BK skimmer and it is certainly the best skimmer I've used and certainly the quietest but it still makes noise, just less than everything else.

As far as price is concerned I honestly don't think you could make the same products for less. I work in manufacturing and machine design, I know what CNC machining costs and what would be involved in making these products, honestly the price isn't that bad and the quality is better than anything else. The problem is that not everyone sees the need for the extra quality, for example their tolerance is 0.005mm!! That is absolutely ridiculous but it sure is cool. If I asked our machine shop to do that they would laugh at first and then come up with a quote so high we would never go through with it.

I don't think the user base is very small, the Canadian distributor can't even keep these pumps in stock, they are usually sold before they arrive. It took about 5 months to get mine. The thing is you don't generally hear positive feedback, but you certainly hear negative. In addition when people pay more they expect more however the relationship isn't linear but rather exponential. For example Hyundai owners don't complain very much about their cars but BMW owners complain all the time. Price aside, BMW is a better car but yet you actually hear more complaints about BMW than you do about Hyundai. It's a funny thing but it's human nature. Nobody is going to take the time to post on such a forum saying "Hey my pump is working great, no issues what so ever".

So skimmers aside, the RD return pump is a good pump and to me, well worth the money. It might not be for everyone but if you care more about noise and quality over price a RD pump may be for you

[albert_dao]

Originally Posted by sphelps

It's a funny thing but it's human nature. Nobody is going to take the time to post on such a forum saying "Hey my pump is working great, no issues what so ever".

LOL!!!! My God, you hit that nail so far through the plank it came out the other side.

*thumbs up

[tlo]

thank you all so much for your opinions and experiences. I am leaning towards a red dragon, but they are soooo pricey. If they really are as quiet as they are made out to be it will be worth it. I am very noise sensitive and what most people tune out as background "white noise" drives me crazy.

[sphelps]

Originally Posted by tlo

thank you all so much for your opinions and experiences. I am leaning towards a red dragon, but they are soooo pricey. If they really are as quiet as they are made out to be it will be worth it. I am very noise sensitive and what most people tune out as background "white noise" drives me crazy.

You could try and find someone local who has one and take a listen for yourself. Even if someone has a BK skimmer, disconnect the air line and you'll get the idea. I'm pretty picky on noise as well and my stand is currently wide open, all I can hear is the skimmer. the pump is very quiet in my books but like you said everyone is different, however I don't think you'll find anything quieter which most people who have compared them would agree on.

One more thing that sold me when I was considering was the fact that these pumps can be used internal! Not much else in comparable flow rate can do that. Running a pump internally usually results in a lower noise level. I ran mine external in the end and I'm glad I did but I always have the option to switch.

[golf nut]

Originally Posted by sphelps

for example their tolerance is 0.005mm!!

.00019" two tenths of a thou on a skimmer?

[sphelps]

Originally Posted by Mr OM

Perfect

At least somebody understands what is required for a sump return.

If you ask a reputable skimmer mfg they will tell you to use a sump pump of the same value as the skimmers capacity, ie if you purchase a skimmer for a 400 gallon system it performs at its best at 400 gph passing across it, any more and its performance will be depleted. The 10 times turnover rate isn't correct if the tank is skimmed properly.

What's required can be very different from what's best or best for certain people. Also the return rate is independent from the skimmer rate. A sump simply extends the display tank, it's the same as putting a skimmer right in the display besides the effect of the overflow. In fact if anything a higher return would result in more surface water in the sump at all times. I can't see how more or less return flow, compared to skimmer flow, would greatly effect skimmer performance. Unless you have it setup some special way, the skimmer isn't skimming 100% of the water that passes by it, and no matter what the flow rate, the % of water skimmed is the same over a given time frame. The only slight improvement here would actually result from more flow, a higher sump turnover would result in less water being recycled through the skimmer. Like previously stated it's a matter of preference, both low and high flow have there advantages but it's a preference not a requirement. There are obviously limits but the range is large. One more reason I see more being better is matching the flow doesn't actually make sense if you look at the numbers. My skimmer for example flows 4000L/h and it's rated for tanks up to 3000L, hmmm so the "required" flow results in a turn over of 1.3

Food for thought: I design and manufacture load cells and weighing systems yet I personally don't use any of them. If I was looking for advice on anything regarding it's installation and real life performance I'd ask the people using them.

Originally Posted by Mr OM

.00019" two tenths of a thou on a skimmer?

That's what's stated regarding the RD pumps, not sure about the skimmer. Keep in mind it likely referring to components relating to the bearings or shafts but it still demonstrates quality.

[golf nut]

Originally Posted by sphelps

Food for thought: I design and manufacture load cells and weighing systems yet I personally don't use any of them. If I was looking for advice on anything regarding it's installation and real life performance I'd ask the people using them.

Please tell me you are kidding, you design something and sell something that you would ask the end user about because you don't know?

My granny has an Audi, she bought it on their 24 Le mans performance, not because it comes in a nice pearl white shade, they don't ask her to drive it around the track and ask for input.