Filtration & Oxygenation

[Jabba]

I have a 1000 litre aquarium, I have been having problems with O2 levels in the tank dropping too low so have been running an 18" airstone at around 400 L/hour Rena 600 both outlets flat out), I also have a Seio M2600 with the venturi fully open but this is damn noisy and the tank is in the lounge so noise matters. (I only have 15 Clown Loach (4 to 7"), 6 Silver shark (6 to 10"), 1 Sailfin Plec (14")in the tank)

For filtration I run an Aquael Unimax Pro 700 and an Eheim 2180.

I want to replace the AquaEL since it's flow rate has always in my opinion been poor - I have been forced to put an Eheim 1260 in line with it to assist but still it doesn't perform well, it has two intakes, one of which is a pig to get going often needing a direct blast from a pump to get the syphon moving but it fails after a time and uses only one of its intakes again so I'm sick of it.

I want to replace it with a filter of similar flow rate to the 2180 but I want to find a way to drive more O2 into the water and the Eheim doesn't fulfil this requirement. I thought about the 2229 wet / dry filter but I am also thinking of going down the sump and PVC pipework route coz I am sick and tired of all these hard to clean hoses clogging up the place a nice neat PVC setup would be much better.

My idea for the sump is for a pair of sealed mechanical filtration sections (independantly servicable) each serving a trickle plate and a common refugium, a place to hide 35 watts of UV and any additional aeration, a place to add chemicals / dosing / carbon etc and a common return from either an eheim or ocean runner pump all fed via a pair of overflows with prefilters (one per sump section) but this lot must be sealed / covered to reduce condensation.

Any ideas - for suppliers of good sumps / overflows - I need to get this done yesterday with a max spend of say £500 or should I just get another 2180 and find another way to do the aeration and plumbing ... how do you plumb PVC onto canister filters ?

 

[Inchworm]

Hi Jabba

Since you don't seem to be having any luck with this thread in Tropical Discussion, I'm going to move it to Hardware and DIY. Perhaps the members who post in there can help you.

 

[rabbut]

Overflow boxes are very un-reliable and usualy leave you with a wet floor, empty sump and burnt out return pump. The only safe way is to drill the back of the tank and install a weir/calfo system.

You could install a sump, but it will be cutting your budget farily fine. You want a minimum of a 250l sump, and unless there is a good tank 2nd hand available at that size to you, you are going to spend about £200 there... Add about £200 for a decent return pump (OceanRunners are ment to be best for sumps, though pond pumps do a good job) £50-75 for the partitioning glass and you don't have a great deal left for pipe, bulkheads and media for filtration, or the drill bit for the hole in the back...

All the best
Rabbut

 

[Jabba]

Thanks,

It is near impossible to drill the tank given that I would need to rehouse the occupants for the drilling, plus the aquarium isn't something that I can move - it took 4 people to put it where it is now so plumbing it in from the rear is a task I cannot consider.

I hear what you say re overflow boxes, I had wondered what would happen if the outflow blocked or was restricted in some way but I planned to use an Aqua Medic C2500 overflow box, it is hideously overpriced but I can't see any way it can possibly overflow to anywhere except the connected pipework since the top edge of the outer tank is a lot higher than the water level in the aquarium if properly set up - given the tanks location leaks I can not afford so am pretty anal about my plumbing .... and another reason for going to PVC pipework.

I plan to have only enough water in the aquarium to fill the sump to capacity and then stop overflowing so the sump will be able to hold an additional 25 to 30 litres should the pump stop and the overflow continue allowing for the overflow taking only the top 8mm of water from the aquarium before the siphon is broken.

I already have a 'builder' looking over a design I have drawn up for a 1 metre long * 0.6 Metre wide * 0.46 metres high this includes for a total of two inflows leading to 2 seperate and independant 3 stage (1 Mechanical and 2 biological) sections allowing maintenance without stopping the system from there to a common refugium before entering the return section. The maximum capacity though I estimated as 200 litres a little lower than you suggested, how is the requirement for sump size determined (I have based it on what I can conceal within the right hand lower cabinet section not on any specific formula)

I already have an Eheim 1262 doing nothing so this would be the pump initially with a float switch to stop it on low water level but I will be buying an additional one, I don't plan to stop using the Eheim 2180 either.

The £500 was a guestimate - I suppose like most of my projects that could be a gross underestimate .... my current tank started as an upgrade from a 4 foot tank and it was planned for it to be a commercial 6 footer, and then it turned into a 7Ft*3ft*3ft custom built .......

 

[rabbut]

You want a sump that is at least 25% of the tank's volume to avoid floods in a power outage, or the pump running dry. As you say, in a power outage, the overflow box syphen tends to break (and on other events, such as partially blocked inlets or air bubbles/maintanance upsetting it) and when flow resumes, the syphen does not, leading to a wet floor...

A confident driller can drill the tank with the water (mostly) and fish still in. The glass particles from drilling are not sharp, and are inert hence making it perfectly safe to do. With a 90o bulk-head, plumbing can be done in-situe with great ease also A Calfo can be set-up by siliconing above the waterline in a partially drained tank also.

All the best
Rabbut

 

[Jabba]

I don't plan on the return section being anywhere large enough to overflow this tank ( I have at least 3" before the tank overflows ) the design of my sump and a float switch will prevent the pump emptying the sump.

But you point out the other crunch .... 'a confident glass driller' .... that isn't me .... glass is 12mm thick pilkington - anybody know any confident drillers nr Glossop / Manchester? any volunteers? .... maybe I should drill the tank anyhow and open my options - I guess that there are fittings that allow you to close them off if not needed.

PS : Can you please post a link to this 'calflo' item

 

[rabbut]

A google search will pull up loads of info on a Calfo overflow system, see here

Any local reef club will be a good place to start looking for a glass driller that will drill the tank in situe. Most marine keepers run a sump, so the drilling of a tank is a fairly regular and routien request for them You could also ask your "builder" since they will likely drill tanks on a regular basis. Most people will do it on industory standord tearms. Basically this means you assume all risk, and if it goes wrong, tough, they'll still want paying The best way to avoid trouble is to ask arround in a local club and find who's drilled the most successfully, and ask that person to drill for you

You can fit valves to the overflows if you wish. My preferance would be quick release PVC, and then you just need a blocker to cover the hole and make the fitting completely waterproof. Valves offer a temperary block also

HTH
Rabbut

 

[Jabba]

I'll ask around, thanks for the info but as for the terms mentioned sorry not in my book, the driller accepts the responsibility if I am paying for the service - I am not a training school or an opportunity for a wannabe to make a fast buck, if they want paying the risk belongs to those charging for the service in my opinion - would you assume all the risk for a plumber or electrician to work on your house - no you wouldn't I'll bet.

 

[rabbut]

Yes, but they will be doing about 2 hours and 15 minuites work for 12mm glass and 3 holes for like £60. That's not exactly a fast buck. It's a slow and grooling buck that's more like a personal favor for the effort involved if you are doing it properly TBH... Plus, doing it in situe makes it harder, as the drillers positioning to the hole isn't directly over the hole as would be ideal... By all means, ask arround, but few will do it for free and comming across someone that accepts all risk for drilling a tank is rare Some say a 50:50 risk split, but even that't unusual...