(stupid?) Return pump question

I bought a second hand drilled tank with a sump...and converted it to a fresh water planted tropical tank.

I feel like I need to have a back up return pump but have no idea what size/brand to buy.

What should I look for? The tank is a 72 gal bowfront with a 20 gallon sump tank. What sort of gallons per hour and lift is usually recommended?

By back up pump, I mean on hand not any sort of redundant (in use) piece of equipment. Though you can bet I'll try using it to speed up pumping old aquarium water out of my 20 gallon wheeled trash can I use of water changes (hate to waste good plant fertilizer)

Thanks for helping me out.

 

The general rule is 10x aquarium size. Where 55 gallon would get a 550 gph pump. However, I feel doing less is fine, I use a 300 GPH pump on my 55 gallon. I use a Sicce pump, with tubing instead of PVC (either is fine).

PVC needs cemented otherwise will get salt buildup where pipes connect as the water seeps through every so slightly but never drips out.

 

Agreed 8-10 times return is good. Keep an eye on head pressure loss. I like life guard pumps. The impellers are very sturdy, cheap, energy efficient, and most are air cooled.

I get something rated for 700-900 gph that will end up giving you 500-700 gph after accounting for head pressure loss. Also keep in mind any 90 degree turn will cut your flow essentially in half.

 

The general rule is 10x aquarium size. Where 55 gallon would get a 550 gph pump. However, I feel doing less is fine, I use a 300 GPH pump on my 55 gallon. I use a Sicce pump, with tubing instead of PVC (either is fine).

PVC needs cemented otherwise will get salt buildup where pipes connect as the water seeps through every so slightly but never drips out.

Thanks! It is currently plumbed with standard silicone tubing clamped onto fittings. No plumbing issues thus far (clamps a bit corroded but with a previous history as a marine tank that isn't a surprise)

 

Agreed 8-10 times return is good. Keep an eye on head pressure loss. I like life guard pumps. The impellers are very sturdy, cheap, energy efficient, and most are air cooled.

I get something rated for 700-900 gph that will end up giving you 500-700 gph after accounting for head pressure loss. Also keep in mind any 90 degree turn will cut your flow essentially in half.

Thanks! Would you base the gallons on the display tank size (72 gal 575-730 gph) or total system volume (~ 85 gal including sump volume 650-850 gph)?

 

What return is on the tank? U could just buy a similar pump. Also DC pumps are nice they can be adjusted to the flow you want

 

What return is on the tank? U could just buy a similar pump. Also DC pumps are nice they can be adjusted to the flow you want

I could! If only I could figure out what I have. I can't find a brand name or model name. There's only the basic required label for electrical equipment. I can't figure out how to translate that into ghp or head height that I see in pump product descriptions.

Thanks for the insight on adjustable (DC) pumps. The fish and I are comfortable with the current flow rate so being able to adjust would be something to look for.

 

Thanks! Would you base the gallons on the display tank size (72 gal 575-730 gph) or total system volume (~ 85 gal including sump volume 650-850 gph)?

Sorry didn’t see the new question. Either one is fine but I generally go with display tank and don’t bother counting the sump since the display tank is where your critters are.

 

OP is using this for a freshwater tank so the turnover rate doesn't necessarily need to be that required for a Saltwater system.
I would recommend anything rated at 550 GPH or more, but make sure (check the labels) that it has a "Max head height" that is well above the height of your tank. Different pump designs have different head heights even though they may be moving the same amount of water measured right at the output. You really want a magnetic drive pump for reliability's sake. Luckily they aren't too expensive. The ones saltwater60 recommended are fine, and Danner also makes a reliable and inexpensive magdrive pump.

 

Agreed I like mag drive pumps. Just look at the head height and GPH graph of the new pump on the box or info on the web and match the flow.
mid you decide on a brand we can help you size the pump if you measure the head height for us.