2 Questions-Can You Help Out a Newbie ?

[joegoersch]

Hello, I have just about finished cycling a 29 gallon tank with a 10 gallon sump. I have a couple of questions, one about filtration and one about nitrates/decay. I hope to get a 120 gallon tank if all goes well and use this as a nurse/quarantine tank.

1) I've read that flow rates should be about ten times the volume of the tank per hour. Does that mean ten times the volume of the display tank or does than mean ten times the total volume (tank plus sump). I'm thinking about getting a bigger sump/fuge and not sure if a mag 5 or mag 3 return pump would be better for the job.

2) With the tank I got a bunch of dead "live rocks." They used to be alive but had been out of water for a month. I put about 45 lbs of this rock in the DT and sump and they were great for cycling, provided plenty of decaying matter to get the ammonia levels up. Now that I'm just about done cycling (ammonia gone, nitrite coming down, nitrates at 40 ppm) I'm wondering if there is any way to expedite getting all the crap off the rocks (decaying algae and god-knows-what in all the little crevices). I scrbbed the rocks before putting them in the tank. How long before this stuff is gone. Will it continue to be a source of nitrates for a long long time ?

I'm going to do some water changes to get nitrates down before adding fish, and I have some chaeto growin--any other thoughts.

Thanks in advance,
Joe

[jimmy frag]

i would do your water change than add a clean up crew to clean off your rock. shouldnt take long before you can add a fish or two

[joegoersch]

i would do your water change than add a clean up crew to clean off your rock. shouldnt take long before you can add a fish or two

Jimmyfrag, Thanks. Can you suggest a crew ? What should I start with ?

Thanks

[kingfisher62]

.

1) I've read that flow rates should be about ten times the volume of the tank per hour. Does that mean ten times the volume of the display tank or does than mean ten times the total volume (tank plus sump). I'm thinking about getting a bigger sump/fuge and not sure if a mag 5 or mag 3 return pump would be better for the job.



I would say 10X the display but you would be better aff at 20X or more.

[billdogg]

If there is still gunk on the rocks that you can see, I would scrub them with a clean brush in a bucket of old tank water (you were gonna be doing a water change or two anyway - might as well put the old water to use before it goes down the drain)

This will allow you to tweak the aquascaping as well.

As far as turnover rate - Tank turnover and sump turnover are not necessarily related. The flow through the sump will be limited by your drain size - you can't pump more out than can drain in. The turnover rate in the tank depends on a couple things - especially sump flow rate and, more importantly, what you plan to keep. SPS require a much higher flow rate than LPS. Most people get the proper turnover using a combination of the sump return, powerheads, and maybe a closed loop.

The return pump can easily be throttled back using a ball or gate valve on the output side. It will not harm the pump in any way - it's no different than a greater head height, and, depending on the pump, may actually use less electricity.

I would purchase equipment with the future in mind - if you are going to upsize - buy larger/better now, rather than buying it twice. Trust me - there is plenty of other stuff you can spend your $$$ on in this hobby!

[greech]

1) I've read that flow rates should be about ten times the volume of the tank per hour. Does that mean ten times the volume of the display tank or does than mean ten times the total volume (tank plus sump). I'm thinking about getting a bigger sump/fuge and not sure if a mag 5 or mag 3 return pump would be better for the job.

Sounds like you are planning on using your return pump for your main source of flow? If you are calculating turnover through the return pump then yes you want to take the entire system volume into account. I only have my experinece to go off of and what I have read but turnover through the sump is supposedly best around 3 to 5 times an hour. The idea being that a slower turnover allows better filtration through longer contact time the water has with skimmer, fuge, etc.

If that doesn't give you enough flow in the tank for corals, etc., the use of powerheads, closed loop, etc are recommended. When gauging which powerheads to use you only need to consider the DT volume. The amount of flow you have in the display via powerheads is dependent on the size of your tank and the livestock you want to keep.

2) With the tank I got a bunch of dead "live rocks." They used to be alive but had been out of water for a month. I put about 45 lbs of this rock in the DT and sump and they were great for cycling, provided plenty of decaying matter to get the ammonia levels up. Now that I'm just about done cycling (ammonia gone, nitrite coming down, nitrates at 40 ppm) I'm wondering if there is any way to expedite getting all the crap off the rocks (decaying algae and god-knows-what in all the little crevices). I scrbbed the rocks before putting them in the tank. How long before this stuff is gone. Will it continue to be a source of nitrates for a long long time ?

I did the same with my BRS rock. Once your tank is cycled, you can add some snails and/or crabs which will help cleanup the debris left on the dry rock. I don't think lingering nitrates will be an issue from the crap on the rocks.

Good advice from billdogg on using the valve in the return line. This will allow you to buy a bigger pump that will work in your larger tank down the road. It's also very helpful in dialing in your return and quieting down your system.

[joegoersch]

If there is still gunk on the rocks that you can see, I would scrub them with a clean brush in a bucket of old tank water (you were gonna be doing a water change or two anyway - might as well put the old water to use before it goes down the drain)

This will allow you to tweak the aquascaping as well.

As far as turnover rate - Tank turnover and sump turnover are not necessarily related. The flow through the sump will be limited by your drain size - you can't pump more out than can drain in. The turnover rate in the tank depends on a couple things - especially sump flow rate and, more importantly, what you plan to keep. SPS require a much higher flow rate than LPS. Most people get the proper turnover using a combination of the sump return, powerheads, and maybe a closed loop.

The return pump can easily be throttled back using a ball or gate valve on the output side. It will not harm the pump in any way - it's no different than a greater head height, and, depending on the pump, may actually use less electricity.

I would purchase equipment with the future in mind - if you are going to upsize - buy larger/better now, rather than buying it twice. Trust me - there is plenty of other stuff you can spend your $$$ on in this hobby!

So what do people really mean when they say "You need ten times the flow rate." Is that flow within the tank ? Is it flow to the sump ? What are people talking about ?

Thanks

[phenom5]

So what do people really mean when they say "You need ten times the flow rate." Is that flow within the tank ? Is it flow to the sump ? What are people talking about ?

Thanks

Best bet IMO/ IME is to run 3-5x of you total system volume through your sump with your return, and use powerheads in the display tank to get you up to 20x turnover of your display.

[billdogg]

^^^ what he said^^^ except that, depending on what you keep, even more flow may be required.

[joegoersch]

^^^ what he said^^^ except that, depending on what you keep, even more flow may be required.

Man, that's a lot of flow. Sand isn't flying around...heck with that flow seems like live rock would be flying around :eek1: