UV install direct to tank question

[akainoa808]

Just working with simple numbers. If I have a 130 gal tank. And I want 3x turn over my pump has to send out at the top 390 gal per hr at the top. Now say I have two pumps one for my manifold and back to the tank. The other pump for my uv then to the tank.

With the attached picture a 130 gallon tank for algae the uv will need 472 gal per hour. And ick etc will need 79 gal per hour.

Does this mean simply that if I am running the uv for algae I would have to turn my other pump off because I am getting my flow rate with just the uv. And if I want to treat for ick the. I would have to have my other pump get the gph into the tank at 311 gph? (390-79)

There would be a vast difference of water flow on each side of the tank for return water depending on what I am doing with the uv.

If I had two pumps on the manifold and sent water through the uv to the tank it would be the same thing.

 

[Doctorgori]

I’m not following you… “two pumps on the manifold”?
did you mean literally ? if so, I don’t think so. I’ll re-read

 

[Doctorgori]

I think I follow. To make a long story short. I have a UV and after much ruminating I concluded one over powered DC pump on a continuous UV was the way to go for me. I just assume adjust flow as needed for whatever come what may …

 

[Privateye]

The flow rates on the chart are the flow rates through the UV sterilizer only.

I also want to note that marine ich requires a dose higher than this chart shows. It's closer to 280,000 microwatts. This unit can deliver that dose but it requires a slower flow rate. Slower flow rate means microbes sit in front of that lamp and their genetic material "cooks" for longer, hence the higher doses. If you need to know the flow rate to achieve this dose then contact the manufacturer.

 

[DJF]

Another thing to consider with uv is not only does it needs to process at a specific gph pertaining to your need but that it should also equate to a certain amount of tank turnover. https://m.liveaquaria.com/article/361/?aid=361

 

[akainoa808]

This is kinda what I am talking about. If the uv requires 400 gph and my out flow is 390 gph. How can I have a second pump?

 

[DJF]

If you only wanted 390 gph in the tank and the uv feed was accommodating what you wanted then you’re right that the second pump would put you over. I guess my question would be why you only want 390gph in the tank or why do you want a second pump? You can probably run the uv slower (more contact time) as long as you were still getting the turnover it needed to be effective.

 

[Privateye]

This is kinda what I am talking about. If the uv requires 400 gph and my out flow is 390 gph. How can I have a second pump?

Your diagram will work. One pump goes through the UV and the other does not. Usually this is more of an issue when someone has one pump that's too strong for the UV. In those cases you install a "bypass". Basically from your pump you split the line with a Y or T fitting with valves on each. One goes to the UV and the other bypasses it. You can have the lines join back together after the UV or not, but having valves on both the UV and the bypass will allow you to control how much of the flow goes to the UV and how much goes around it.

 

[akainoa808]

If you only wanted 390 gph in the tank and the uv feed was accommodating what you wanted then you’re right that the second pump would put you over. I guess my question would be why you only want 390gph in the tank or why do you want a second pump? You can probably run the uv slower (more contact time) as long as you were still getting the turnover it needed to be effective.

I am gone from home half the time. I need a tank that is as safe as I can make it. Preferably id like to have two pumps on the manifold with a one wave valve on each pump before they get to the manifold. This was if one pump dies the other pump can take over. and due to the one way valves once push water through the dead pump. Or even have it set up so only one pump is running and when it dies APEX kicks the other one on.

 

[akainoa808]

If you only wanted 390 gph in the tank and the uv feed was accommodating what you wanted then you’re right that the second pump would put you over. I guess my question would be why you only want 390gph in the tank or why do you want a second pump? You can probably run the uv slower (more contact time) as long as you were still getting the turnover it needed to be effective.

I read i would want anywhere from 3x to 4x turn over in my tank. Thats why I only want 390 gph back to the tank. Am I correct in this thinking?

I will be away from my tank for weeks at a time constantly. I want it to be safe as possible. If I am able I would like to put two pumps on the manifold.

 

[Privateye]

3-4x sounds a bit on the safe side to me, but I haven't exactly tested it. It's probably pretty microbe-specific too. Like, if you're trying to remove green water from a pond you're fine at a 0.5-1x turnover per hour through a properly-sized UV.

 

[DJF]

I read i would want anywhere from 3x to 4x turn over in my tank. Thats why I only want 390 gph back to the tank. Am I correct in this thinking?

I will be away from my tank for weeks at a time constantly. I want it to be safe as possible. If I am able I would like to put two pumps on the manifold.

Total turnover you could go higher. Turnover thru the UV could be dialed to 3-4x and another 2-3x from a 2nd pump.