Troubleshooting 300 Gallon Filtration

[Arrow1oo]

So I have a brand new 300 gallon tank that I stumbled upon. It’s 8’ long x 2’ wide x 29” tall.

I’ve decided to keep some SA cichlids, so I want some decent filtration to be able to keep up with that. My tank is bottom-drilled and with the appropriate bulkheads will fit 2 1" and 2 3/4 pipes. I initially was going for a herbie setup with the 1" holes as drains and the other two as returns, but I'm seeing online that the maximum turnover I'll get with this is maybe 2-3x (700 - 900 gph).

I'm a freshwater guy so I'm used to plugging in canisters and getting 6-8x turnover, but is this an acceptable turnover for a sump (was planning on using a 75 gallon sump)? I'm starting to wonder what the tank was drilled for initially.

As of now, my options are:

1. Run with the sump of 2-3x turnover but tons of media to compensate

2. Run with the sump as planned but plumb an fx6 into the display tank as well to help increase turnover

3. Ditch the sump altogether and just go with a few fx6's

Would really appreciate any help with this. Initially was inspired to make some type of refugium/sump from duanes so shoutout to him for being awesome

 

[danotaylor]

The size of the pipes plumbed in for drains & returns is relevant to achieving certain flows, but you neglected to mention the gph of the return pump/s you intend to use.
The overall turn over is determined by the flow rate of the return pump/s and the head height they have to overcome.
I have twin sumps in my 10 foot long 500 gallon tank w a 5000 GPH pump in each sump that has to overcome 60 inches of head height to return the water to the main tank. My total flow out of each sump ends up being about 1500 GPH.
Don’t get sucked into requiring super high flows. Contact time with your media is most relevant when it comes to biological filtration. You cannot compensate for anything by adding “tons of media“ as the beneficial bacteria can only colonize to the size of the available food source. You only need sufficient media for the beneficial bacterial colony. In the absence of anything to remove nitrate, such as the living sumps that duanes uses, or something like chemipure blue, your only option for removing nitrate is water changes. All very high flows achieve is water polishing and mechanical filtration. You could use some circulation pumps or wave makers in the main tank to lift solid waste to the overflows and to provide the necessary, water movement to keep your inhabitants happy.

 

[duanes]

I use a 1500 gph pump using 2 one inch PVC drains.

I don´t use drill holes for returns, but run PVC returns above the rim of the tank, to create and much turbulence at the waters surface as possible,
To those drill holes are much mor evaliable as outflow ports

I consider canister fitraion totallly inadequate compared to a sump, and even though I own a couple of cans, those that came with the tank, I only use them as door stops

 

[Arrow1oo]

Gotcha, good stuff here so I appreciate you both.

Honestly danotaylor , as far as return pumps go I’m willing to go with as powerful a pump as I need.

I was looking at Jebao DCP pumps, I plan on running two for redundancy (one for each return). Ideally, I’d like a model powerful enough that I can run it at partial capacity (don’t want to throttle 100%).

With my intended setup:

2 1” drains Herbie-style (one siphon and the other as emergency)

2 3/4” returns with 2 of whatever pump size would be best (was looking at the jebao dcp-10000 or dcp-15000

Would you say that alone would do the job?

duanes I agree the sump just seems better in every way. For your two 1” drains, are they both submerged or do they follow the herbie setup as well?

 

[duanes]

My outflow ports sit fairly close to the waters surface, I drill to reflect that high to make use if that
I have had tanks drilled on the bottom, and with those I have used stand pipes, cut to where I want the waters surface to sit.

you can see, the standpipe on the right, and see the pvc plumbing underneath th tank

The same tank, you can see there are 2 PVC stand pipes, one left one right.
And as usual, the influent is run above the rim, no need to use the drill holes
I find without stand pipes on bottom drilled tanks, its harder to control water flow.

 

[Arrow1oo]

View attachment 1570108
My outflow ports sit fairly close to the waters surface, I drill to reflect that high to make use if that
I have had tanks drilled on the bottom, and with those I have used stand pipes, cut to where I want the waters surface to sit.
View attachment 1570109
you can see, the standpipe on the right, and see the pvc plumbing underneath th tank
View attachment 1570111
The same tank, you can see there are 2 PVC stand pipes, one left one right.
And as usual, the influent is run above the rim, no need to use the drill holes
I find without stand pipes on bottom drilled tanks, its harder to control water flow.

Awesome, thanks for the breakdown.

You’ve brought up returning over the top over the rim and it’s sparked some ideas for me.

What if instead of a herbie setup I go for a Bean Animal, using the two 1” drains (primary and secondary) and one of the 3/4” holes as an emergency.

My last 3/4” hole can be a return and I’ll have a second return over the rim like you often do.

Shouldn’t this give me:

1. The same near-silent operation as the herbie

2. More GPH since I have two drains working rather than one.

3. Enough return power to match my pumps to my drains.

 

[duanes]

That´s what I would do with the 4 holes.

 

[Arrow1oo]

That´s what I would do with the 4 holes.

Think this is the plan then. Not sure how much of an increase in GPH I get from the secondary drain but I’ll take what I can get, it’ll help.

Also, what sizing do you suggest I use for my primary, secondary, emergency.

I have two 1” pipes so one of the three will need to be 3/4”. Is it greedy and unsafe to use th two 1” pipes as primary and secondary drains with the 3/4” being the emergency?

 

[duanes]

I always like to use the largest bore PVC pipes that fit with the bulkhead.
If 1¨ pipe screw/friction fit into the bulk head that what I use, for the simple reason smaller bores can plug up with debris faster.
All it takes ia couple snails and some crud and things start toback up.
I like threded bulk heads

And with any extended length of PVC, like to place unions, every couple feet to be able to ream out debris that easily van get caught.


I also like screens that can be easilybrushed of rinsed out to prevent back ups.
These 2 thread into my 1¨ bulk heads, and usually need to be brushed out every other day ir so to prevent clogging.


Because I consider the planted sectio to be the most important part of my sump filtration.
below os my 125 gal sump.

As you can see, the pump, a couple tiny bags of biomedia, and some porrett foam, do a small portion of the mechanical and biofiltration in the sump, the rest, (the majority) is done with aquaric plants.