Determining flow

[ShepherdTech]

Flow is an important element for keeping corals. I have the Neptune PMK for determining PAR at a specific location, yet I am unsure of how to determine the same for flow. Is everyone just winging it and hoping for the best, or is there some secret tool or method besides watching the coral, to determine the flow. Also, if there is no way to measure it (FMK does not do this), what medium flow is to one person, that might be high or low flow to someone else, no? I’m a data person who likes to know precisely what I am doing (IT career), so I do not like guessing at things. Maybe the hobby (or parts of it) still involves guesswork like it did when I was last in it (12-15 years ago and not nearly as in-depth as I am now).

 

[Mjrenz]

Flow is an important element for keeping corals. I have the Neptune PMK for determining PAR at a specific location, yet I am unsure of how to determine the same for flow. Is everyone just winging it and hoping for the best, or is there some secret tool or method besides watching the coral, to determine the flow. Also, if there is no way to measure it (FMK does not do this), what medium flow is to one person, that might be high or low flow to someone else, no? I’m a data person who likes to know precisely what I am doing (IT career), so I do not like guessing at things. Maybe the hobby (or parts of it) still involves guesswork like it did when I was last in it (12-15 years ago and not nearly as in-depth as I am now).

There's really is no magic number, every tank is unique. There's a lot of factors that play into it such as tank size, aquascape, and the types of corals you keep. I've found the best thing to do is make small adjustments to flow and coral placement and your corals will tell you if they're happy or not

 

[ShepherdTech]

There's really is no magic number, every tank is unique. There's a lot of factors that play into it such as tank size, aquascape, and the types of corals you keep. I've found the best thing to do is make small adjustments to flow and coral placement and your corals will tell you if they're happy or not

That is another thing I alluded to, there is no way to actually determine a number. I sort of hoped someone had a trick up their sleeve for determining which areas of their tank offered similar flow. I don’t know of a way to do that, but you can determine the path air takes by smoke, release due into liquids to watch flow or find leaks (not substances I would put in my reef tank).

 

[Mjrenz]

That is another thing I alluded to, there is no way to actually determine a number. I sort of hoped someone had a trick up their sleeve for determining which areas of their tank offered similar flow. I don’t know of a way to do that, but you can determine the path air takes by smoke, release due into liquids to watch flow or find leaks (not substances I would put in my reef tank).

I'm sure there is some type of scientific approach that could be taken but I'm not sure what would be reef safe

 

[KStatefan]

You could use some type hand held flow gauge.

 

[Dripdroppin]

Nothing beats the good ole eye test imo

 

[jda]

You kinda got to use the eye test, or trust people who have had success before you. Every tank is different and not everybody runs all of their pumps at once so the LPH or GPH stuff is a joke.

Wavebox, for example, moves 100% of the tank water all of the time, but does not blow anything around. Flow pumps vary from strong to weak and wide to narrow and static to dynamic. Gyres move a lot of water, but they are not dynamic.

This is one where you are just going to have to let go and wing it. There are no tools to help you. I have a masters in engineering and wrote more code than anybody and I can tell you that the more that you tighten your grip the more that you will lose. Skip the data level (data is useless until it is turned into information by a human) and even skip the information level and go straight to the knowledge level for this one - post your tank size and see what other successful people are using on this size of tank... the kind of success for 5+ years.

 

[ShepherdTech]

You kinda got to use the eye test, or trust people who have had success before you. Every tank is different and not everybody runs all of their pumps at once so the LPH or GPH stuff is a joke.

Wavebox, for example, moves 100% of the tank water all of the time, but does not blow anything around. Flow pumps vary from strong to weak and wide to narrow and static to dynamic. Gyres move a lot of water, but they are not dynamic.

This is one where you are just going to have to let go and wing it. There are no tools to help you. I have a masters in engineering and wrote more code than anybody and I can tell you that the more that you tighten your grip the more that you will lose. Skip the data level (data is useless until it is turned into information by a human) and even skip the information level and go straight to the knowledge level for this one - post your tank size and see what other successful people are using on this size of tank... the kind of success for 5+ years.

Data is a point of reference for anything. You simply cannot compare what someone else is doing to something you are doing if there is not a point of reference. You can get the same exact equipment, but the flow will always be somewhat different due to aquascaping, powerhead placement/direction, etc. I didn’t really think there is an answer or method for this, but it really would’ve been a nice surprise. It’s faster and easier for me to experiment myself, than try to mimic someone else’s tank, not having any clue where in the tank I will have the same flow as they do. I really am surprised someone hasn’t developed some type of instrument made for an Apex connection to determine and map flow of an area over time, regardless of how useable it would be. We are in a time of gadgets and information galore!

 

[jda]

The point of reference is the tank dimensions and types of pumps. Give your tank dimensions and you will get some good pumps to start with. People figured out the best positions for most pumps. It will help. Knowing what you are trying to keep will help too.

I would have written the same thing about twenty years ago, but after having sold a tech startup to the arguably the #1 tech company (and having to work for them for 4 years) and having a reef tank for years, I learned that data is just a starting point and control is an illusion. Neither are worth much... alone. Also, data that you did not collect is rarely good - most people don't get this, but it is SO true. I once wrote a my own reef "controller" in ubuntu on a MacMini with j2ee and ruby where I could ssh from my phone, it backed it's self up and could run out of AWS if the mini went down, etc. I had a battery array that could run the tank for like 6 hours (24 without the lights). I wrote gbs of data to mysql thinking that it would help. I had a best-two-of-three probe module for temp, pH and even ORP. True redundancy and failover. All a waste of time... even when it could detect a problem, there was nothing that I could do about it, so I got rid of it all.... and this made an apex look like a joke. The code is on github if you want it. All that it did was control me, not the tank. It was an OK monitor, but I had good equipment that never failed. I run a Ranco for redundancy on my heaters now, but no other controller.

I think that if you are still reefing in a decade, you will likely come to the conclusion that the less that you are involved with control or thinking, the better. Just buy good equipment that is well-used, time-tested and recommended by successful reefers and let it go, then factored/chosen for your own situation at a high level (without thinking too much). Then, let the bacteria and other microfauna do their thing - they are better at it than you are.

I had to make this paradigm shift, but it changed my life for 100% the better in all phases... I was a better engineer, father and hobbyist.

...so what size of tank do you have, and what do you want to keep?

 

[ShepherdTech]

The point of reference is the tank dimensions and types of pumps. Give your tank dimensions and you will get some good pumps to start with. People figured out the best positions for most pumps. It will help. Knowing what you are trying to keep will help too.

I would have written the same thing about twenty years ago, but after having sold a tech startup to the arguably the #1 tech company (and having to work for them for 4 years) and having a reef tank for years, I learned that data is just a starting point and control is an illusion. Neither are worth much... alone. Also, data that you did not collect is rarely good - most people don't get this, but it is SO true. I once wrote a my own reef "controller" in ubuntu on a MacMini with j2ee and ruby where I could ssh from my phone, it backed it's self up and could run out of AWS if the mini went down, etc. I had a battery array that could run the tank for like 6 hours (24 without the lights). I wrote gbs of data to mysql thinking that it would help. I had a best-two-of-three probe module for temp, pH and even ORP. True redundancy and failover. All a waste of time... even when it could detect a problem, there was nothing that I could do about it, so I got rid of it all.... and this made an apex look like a joke. The code is on github if you want it. All that it did was control me, not the tank. It was an OK monitor, but I had good equipment that never failed. I run a Ranco for redundancy on my heaters now, but no other controller.

I think that if you are still reefing in a decade, you will likely come to the conclusion that the less that you are involved with control or thinking, the better. Just buy good equipment that is well-used, time-tested and recommended by successful reefers and let it go, then factored/chosen for your own situation at a high level (without thinking too much). Then, let the bacteria and other microfauna do their thing - they are better at it than you are.

I had to make this paradigm shift, but it changed my life for 100% the better in all phases... I was a better engineer, father and hobbyist.

...so what size of tank do you have, and what do you want to keep?

I get it, but also just like having data. I’m not the type to obsess over it, but like with the PAR meter, it is nice to look at what the reading is and compare it with other locations when that reading changes and relate it to changes.

I have a 220 gallon and plan to have a mixed reef, which so far is zoanthid, blasto, some softies and the like. Running two Neptune WAVs, since I got tired of waiting in the XF350 Gyres and cancelled/refunded the order.

 

[jda]

Two 350s are way too much for that tank, IMO. I have one on a 240 and they are too static and move too much water and I only run them on about 25% or else my acropora start to lean as they grow. Just a single one at 100% made my fish have to work too hard to swim once it got going. I think that you got lucky here. The are too static for me once the corals get larger - they affect the growth patterns. I am not a huge fan, but I do have other pumps in the tank to help with dynamic flow.

The beauty with adjustable pumps is that you don't have to get it right at first.

Those kind of corals don't need a ton of flow, so definitely make sure that your fish are not super-skinny from having to work too hard to swim. Sand should not be moving around. You should be able to see the polyps on your corals and watch them move. Make sure that the corals have some movement and an occasional minor blast, but are not thrashing and refusing to extend. You will have dead spots even if you put a boat motor in there, so just get over that and use the opportunity to just siphon out the crud that develops in these spots. Let the corals and fish be your guide. You will easily be able to tell what is right.