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Avast Marine
07/17/2014, 02:25 PM
OK, so since we have had a little discussion on design goals and objectives when designing new products in the feeder thread herehttp://www.reefcentral.com/forums/showthread.php?t=2372944 I want to open up a discussion about a product that has a much, much closer release date :)

So I am going to outline the design goals again and let you know where we are on a few things and open it up for discussion.

1. Does it solve the problem?

Yes. We have a design that allows a full 1 liter of biopellets to be fluidized very hard while limiting the through flow to the ideal range in a standard MR5 reactor. What is the ideal range and how did we come up with it? I will address that in a separate post but for now, lets just say it solves the problem.

2. Is it reliable?

Yes. It actually reduces maintenence of filter screens and clogging. We have chosen to use a very reliable Sicce Silence pump for the re-circulation.

3. Is it easy to use?

Yes, it is plug and play. It can even be sold as a retrofit to existing customers who already have a media reactor from us, this was it's own separate design goal btw. It may be able to be used as a retrofit on some other manufactures media reactors (more on that later). We have not decided if we are going to offer a part kit or not for this. If we do it, will probably be several months after we release the AVAST built version. We do this so we can learn how to build and assemble them really, really well. It makes writing instruction manuals and troubleshooting much easier down the road when we do offer things in kit form.

4. Does it look good?

Hard plumbing, integrated valves, painstaking effort taken to color match with our existing product line. Sexy.

5. How much is it going to cost?

Less than anything that is currently on the market that actually works. More savings can be had with pairing the recirc kit to a diy reactor or using existing reactor. We are hesitant to decouple the pump from the kit though because there is such a wide variety of fittings used and configurations of all the different pump manufactures and we have chosen what we feel is the best out of the box solution for this application.

6. Is there a market for it?

I think so. There is nothing comparable on the market although there are a few recirc biopellet reactors. It is hard to gauge how big the market is but you tell us!

7. How much investment does it require to bring to market?

Medium. We have to order a pretty substantial amount of inventory to meet MOQ's on some of the parts and others we will order more than we need to get better price breaks, this will lead to the lowest possible cost for our customers. There are a few custom fittings we need that don't exist as a commodity item, so those need to be manufactured. There are 3 sizes of reactors we make so we will probably limit initial tooling and ordering to the MR5 size which will be good for a 200g tank (most of the market and our best selling size). Plus eventually we would like to have some sort of universal kit that attaches to other manufactures media reactors although that is a lower priority.

So now that's out there, but the product release date is still not decided. We are in the long term testing phase of the units and are getting ready to move forward with production since testing has been fantastic. We still have plenty of opportunity and time to consider any ideas or concerns anyone has though or just talk about the hows/whys etc of running biopellets in a recirculating reactor rather than a single pass.

Avast Marine
07/21/2014, 12:28 PM
So what is the optimal flow rate for a recirculating biopellet reactor? First we have to define the goals, in this case the first goal is to achieve the longest possible contact time with the tank water and the media. The second goal is to make sure all of the water comes in contact with the media during an average day.
To determine the formula for this we will look to the works of P.R. Escobal who is one of the most well respected scientists and engineers with regards to modern aquarium systems. In his reference manual, Aquatic Systems Engineering he provides us with the following equation to solve this problem:

T=a(G/F)

where:
T= time, the number of hours for all water to pass through a given device
F= flow rate through the device (GPH)
a= Purity coefficient. This is a constant based on the percentage of total tank water that you want to pass through the device.
G= Total system volume in gallons.

Lets look at the Purity coefficient in more detail as that is the one most willl likely not understand in the formula. This is a fixed number from another more complex formula but the easiest way I can explain it is something like this:

The first number represents the constant and the second number represents the percentage of water filtered during the defined time (T).

4.6 = 99%
6.9 = 99.9%
9.2 = 99.99%

Next, lets look at time (T). We are going to use 24 here, for 24 hours.

Now we have enough information to solve the equation. We are going to use a 200g system running 1 liter of biopellets as our example and a purity coefficient of 6.9


T=a(G/F)
24=6.9(200/F)
F=6.9(200/24)
F=57

Flow rate = 57gph.

If we solve the above using the 99% and the 99.99% coefficients we come up with 38gph and 77gph respectively. We consider this the ideal "range". The conclusion of all of this is that we can see that if we want the longest possible contact time combined with highest percentage of water flowing through the media, the optimal flow rate is going to be between 38-77gph. Our advice would be to not get hung up on the "exact" number but instead shoot for something in this range.

So why a ricirculating biopellet reactor? You simply cannot fluidize 1 liter biopellets with a 38-77gph flow rate. This means you are not maximizing the contact time with the media to it's true potential.

I present the following scenario and equation:

Same 200g tank running 1 liter of biopellets at 350gph to achieve fluidization.

T=a(G/F)
T=6.9(200/350)
T=3.94
Time=3.94 hours.

So you still achieve the same 99.9% of water going through the reactor but it happens in 4 hours instead of 24.

Conclusion: A recirculating biopellet reactor increases contact time with the media by 600% during the course of a day. This maximizes the effectiveness of the media to it's true potential without clumping or sacrificing contact time.

msderganc
07/25/2014, 03:53 PM
Hi Dan,

Interesting analysis and I'm looking forward to the reactor.

However, one of your assumptions is that contact time is important with biopellets - is there research that indicates this?

Also, the time period of 24 hours seems arbitrary. If there is research on contact time, wouldn't you want to optimize the flow rate to the ideal contact time? Put another way, what if the ideal contact time is longer or shorter than what you've assumed?

twatkins521
07/26/2014, 04:23 AM
Have you guys looked at the Reef Interest All in One BioPellets?

It would be nice to have a reactor design that effectively tumbles these per the manufacturers recommended flow rate which is significantly higher than virtually all the other biopellets on the market. I think they recommend somewhere between 525 gals to 700+ gals per hr for 2 liters of BPs.

I am running these in one of your MR10s plumbed into my CS3 skimmer. Getting that much flow thru the reactor is nearly impossible without modifications. Installing a tee to bleed off some of the output from the reactor to the skimmer helped along with bigger tube fittings but it is still not optimal.

I have been looking at other media reactor designs to address the flow issue. A Recirculating design seems to increase contact time and fluidization in the reactor but I am not sure it does much for flow rates. With these BPs, flow rate seems to be king over contact time. Having a design to address both contact time and flow rate would be great.

I'ld like to see a recirculating design that can handle increased flow rates, has a non-flat bottom of the reactor to promote better mixing, and a improved way of loading the BPs into the reactor.

Just my two cents and wish list...

Avast Marine
07/26/2014, 06:29 AM
Have you guys looked at the Reef Interest All in One BioPellets?

It would be nice to have a reactor design that effectively tumbles these per the manufacturers recommended flow rate which is significantly higher than virtually all the other biopellets on the market. I think they recommend somewhere between 525 gals to 700+ gals per hr for 2 liters of BPs.

I am running these in one of your MR10s plumbed into my CS3 skimmer. Getting that much flow thru the reactor is nearly impossible without modifications. Installing a tee to bleed off some of the output from the reactor to the skimmer helped along with bigger tube fittings but it is still not optimal.

I have been looking at other media reactor designs to address the flow issue. A Recirculating design seems to increase contact time and fluidization in the reactor but I am not sure it does much for flow rates. With these BPs, flow rate seems to be king over contact time. Having a design to address both contact time and flow rate would be great.

I'ld like to see a recirculating design that can handle increased flow rates, has a non-flat bottom of the reactor to promote better mixing, and a improved way of loading the BPs into the reactor.

Just my two cents and wish list...

The all in one biopellet is heavier and that is why they recommend a higher flow rate, to tumble the pellets (they actually say this in thier literature). It has nothing to do with optimal flow rate for media contact time. By recirculating with a 500-600gph pump you can achieve fluidization while retaining a effluent rate that is closer to ideal. This is in essence part of the industry's casual attitude which leads to consumer confusion, they are the manufacture of the media but provide a flow rate recommendation based not on observation rather than sound chemistry. They do this of course because the options for using the media correctly are cost prohibitive for most and they are trying to market their product to a large base.

Msderganc, I will answer you question next week as I want to have time to go into more detail than I have time for now.

msderganc
08/12/2014, 10:03 PM
Any idea when you'll be releasing this? I think I'm in the market for one....:-)

lovetoreef
09/03/2014, 12:24 PM
any news on this front?

Avast Marine
09/04/2014, 10:54 AM
Yes, we decided to go for a reverse release on this item. Meaning, we will be offering retrofit kits for current owners first, then have the complete reactor available shortly available after that. We are starting with MR5 kits and then will do MR10's and 16's. MR5 retrofit will be available this week and the first release is earmarked as retrofit only. The full release will be about 3 weeks from now on the MR5 and then we will do the same process with MR10 and finally MR16.

msderganc
09/04/2014, 11:03 AM
Awesome! Do you know approximate dimensions? And any idea of the price for the full setups?

starionesir
09/05/2014, 06:35 AM
So when will the MR5 retrofit kits be available? I see you said they will be available this week but didn't see them listed on your site anywhere. I've got two of the MR5 reactors and would love to convert them.

rjallen
10/04/2014, 11:35 AM
See that no one has answered you. I guess you know the kit for the MR5 is NOW listed and available for purchase and has been for about 10 days. Check their site. I just completed a water test for my MR10 and it passed. Avast emailed me the kit for the MR10 will be available about 3 weeks from their release of the MR5 kit.

RJA

starionesir
10/08/2014, 01:36 PM
Thanks for letting me know. I do have there kit running. Avast emailed me the day it was available. Working good so far.

cubiclewarrior
12/02/2014, 03:46 PM
You forgot to mention the AVAST logo is just Bad A$$ and adds to the look of your sump!

MRCYCS805
02/09/2015, 03:17 PM
I'm looking to buy this with the mr5 reactor but only see both sold separately are these going to be available in 1 kit soon biopellet recirculating setup and reactor in the your build catagory

PatrikD
02/15/2015, 09:09 AM
Is the complete recirculating reactor available?

MRCYCS805
02/15/2015, 10:07 AM
Is the complete recirculating reactor available?
I just ordered one last week had to get the mr5 and the recirculating kit separate should be here on Tuesday can't wait

starionesir
02/24/2015, 01:20 PM
I have one. It works great. Was a no brainer being I already have two of the MR5 reactors. Was nice to be able to convert one instead of having to buy a whole new setup.

MRCYCS805
03/12/2015, 08:58 AM
I just set mine up :) has anybody used the 1/8" barbed fitting on the top for their by-product to skimmer I was thinking of eliminating the T and using it as my by product drain

Avast Marine
03/12/2015, 05:21 PM
I just set mine up :) has anybody used the 1/8" barbed fitting on the top for their by-product to skimmer I was thinking of eliminating the T and using it as my by product drain

I don't see any reason why this wouldn't work provided you are able to get enough flow through it. Here is a link to the flow rate calculator: https://docs.google.com/spreadsheets/d/1BedjGN1axxGlHr_I0H108Tpg-87_VXCflWDaJTsK9-E/edit#gid=0

MRCYCS805
03/12/2015, 05:56 PM
Nice thanks im going to try it out. I Downloaded the calculator and now am trying to understand it lol i input my water volume and get
6.9 - Constant Coefficient And
39 - Flow Rate (gph)

Now my question what is Constant Coefficient ? And is the gph the amout of by-product "effluent" i believe, recommended for my size tank ?

Avast Marine
03/13/2015, 08:25 AM
The formula is discussed in detail in the second post of this thread. Yes, 39gph is the effluent flow rate (by-product).

MRCYCS805
03/13/2015, 08:26 AM
The formula is discussed in detail in the second post of this thread. Yes, 39gph is the effluent flow rate (by-product).
Cool thanks