New return pump questions..

[KreativJustin]

So I got a 75 that has an older style sump system in it that I am going to use for the time being until I can upgrade to a new sump down the road. The pump that it came with is super weak (265gph) for a 75 gallon tank (not sure why he had it so low or if he actually used it). So I am looking online for a new return pump. I was planning on getting an 880gph and using a 3/4 hose to return it to the display tank, almost 4ft head lift, and single return. This pump does allow to turn the GPH down, but I am more concerned with actually getting enough flow bc I have heard that the head lift will drastically slow down the GPH. This is a freshwater tropical tank btw, not setup, still in the planning stage. I put a link to the pump at the bottom.

So my question(s):

How do I measure the actual GPH (and be fairly close) without having to buy a special tool to measure it?
Does splitting and having two returns slow down the pump GPH?

Any and all help is appreciated, this is my first stab at a sump!

Thank you in advance.


https://www.amazon.com/gp/product/B01CGAD986/ref=ox_sc_act_title_1?smid=A1ZOTI9DDE28NV&psc=1

 

[Andy Sager]

So I got a 75 that has an older style sump system in it that I am going to use for the time being until I can upgrade to a new sump down the road. The pump that it came with is super weak (265gph) for a 75 gallon tank (not sure why he had it so low or if he actually used it). So I am looking online for a new return pump. I was planning on getting an 880gph and using a 3/4 hose to return it to the display tank, almost 4ft head lift, and single return. This pump does allow to turn the GPH down, but I am more concerned with actually getting enough flow bc I have heard that the head lift will drastically slow down the GPH. This is a freshwater tropical tank btw, not setup, still in the planning stage. I put a link to the pump at the bottom.

So my question(s):

How do I measure the actual GPH (and be fairly close) without having to buy a special tool to measure it?
Does splitting and having two returns slow down the pump GPH?

Any and all help is appreciated, this is my first stab at a sump!

Thank you in advance.


https://www.amazon.com/gp/product/B01CGAD986/ref=ox_sc_act_title_1?smid=A1ZOTI9DDE28NV&psc=1

The formulations in this link should help: https://www.simplicityaquatics.com/...timate-the-head-pressure-on-your-return-pump/

Here's a link to an online calculator: https://pentairaes.com/pump-calculator

 

[Colin_T]

If you have the pump, you can measure the water flow by having it pump water up to the height required, and timing how long it takes to fill a 20 gallon bucket. Then work that out to how many gallons per minute, then convert it to gallons per hour.

Splitting the line so there are 2 lines going to the tank does reduce the flow rate a bit.

----------------

The pump on Amazon uses a lot of power (100 watts). This equates to about 2400 watts per day and that will add to your power bill. Can you find something that is more efficient?

My old AquaClear 800 powerhead only used about 6 watts. It didn't pump as much water as the pump you are looking at, but there has to be something in between which is going to pump the water you need but not need a power plant to run.

 

[KreativJustin]

If you have the pump, you can measure the water flow by having it pump water up to the height required, and timing how long it takes to fill a 20 gallon bucket. Then work that out to how many gallons per minute, then convert it to gallons per hour.

Splitting the line so there are 2 lines going to the tank does reduce the flow rate a bit.

----------------

The pump on Amazon uses a lot of power (100 watts). This equates to about 2400 watts per day and that will add to your power bill. Can you find something that is more efficient?

My old AquaClear 800 powerhead only used about 6 watts. It didn't pump as much water as the pump you are looking at, but there has to be something in between which is going to pump the water you need but not need a power plant to run.

Can you recommend a pump for a 75 gallon? I'm probably closer to 3' head, but I say 4' for cushion room (if I can turn it down).


I actually filled the tank up yesterday and found a leak

 

[Colin_T]

I have no idea what pumps are around now. Maybe Google search for Eheim hobby pumps, Fluval water pumps and pond pumps and check the power rating and flow. See if there is something with good water flow but not power hungry.

If the tank has a leak, mark it with a permanent marker, drain the tank, dry it with a towel, leave it for 24-48 hours to dry properly, the use some aquarium silicon to patch it. The aquarium silicon should be allowed to dry for 7 days before filling although most people only wait a couple of days if it's just a small patch.

 

[KreativJustin]

I was reading that I would have to strip down all of old silicone before putting new one and that I cannot just clean that area and put new on top. I have no experience in resealing aquariums, and the thought of 75 gallons of water on my hardwood floors scares the s*** out of me. I've read horror stories of people not resealing right and the tank blowing out.

It is just a tiny spot and I did mark it, and drained it to under that point to see if it was leaking from the bottom too, and it appears that it only leaks from that one spot. Very tiny leak.

 

[Colin_T]

Check the silicon between the glass. If it's just a tiny hole you can normally patch it.

Bad silicon is cream or white and could have bubbles in it. It will also be hard and sometimes brittle.

Good silicon is clear or nearly clear unless it's black silicon, then it should be black and have no white or cream areas in it. Good silicon is firm to touch but slightly squishy.

Post pictures of the edges of the tank (here or on the other thread) and I will have a look. But most of the time a tiny hole just needs a bit of silicon and your good to go.

 

[KreativJustin]

Ok, I'll take a picture tonight. I am thinking the edges were creamy looking though (on the outside - not the inside) That is probably bad, right?