1750gph on a 75g tank with 30g sump?

[cchhcc]

I agree

With the sump you only have a 16.6 turn over rate. 75g + 30g = 105g--1750/105= 16.6

I allways try to aim for 10-15 turn overs per hour on my tanks. Just because it keeps the tank debris free. But it is not needed if you are just after supreme bio-filtration. That can be done with very low turn over rates.

Your problem seems to be current and not flow. So like mentioned you need to distribute the flow more. I would build a 3/4" spray bar the entire length of the tank. And install it in the back top, right under the trim. Put you a 3/16" hole in the bar every inch or so. Aimed down in the tank 20 degree's or so from the water surface. And you will be set.

Very good post!

Yes, the larger you can make the return line the less focussed the flow will be (even if the volume is the same). A big return line, plus a big spray bar, plus lots of big holes in the spray bar will spread the flow the best.

You should be able to valve down the flow at the pump with a ball valve. That may be what you mean by the "knob" reference.

Also, a pump can only flow as much as the tank can drain, so unless you valve it down you will starve the pump and possibly overflow the tank.

All that said, as long as there's a place of refuge from the strongest current, you'd be surprised how well cons will do with flow. They can be found in every type of CA water, including fast flowing streams.

 

[vaine111]

Or you can scrap it so it's not eating up your electric bill.
Or get a bigger tank.

 

[Mercury2234]

Very good post!

Yes, the larger you can make the return line the less focussed the flow will be (even if the volume is the same). A big return line, plus a big spray bar, plus lots of big holes in the spray bar will spread the flow the best.

You should be able to valve down the flow at the pump with a ball valve. That may be what you mean by the "knob" reference.

Also, a pump can only flow as much as the tank can drain, so unless you valve it down you will starve the pump and possibly overflow the tank.

All that said, as long as there's a place of refuge from the strongest current, you'd be surprised how well cons will do with flow. They can be found in every type of CA water, including fast flowing streams.

The cons are just there as a "test" out fish; I am planning on stocking with some marble gars (1-3, deciding, havent bought one yet), a 5" clownknife (as a growout tank), and a 6" senegal bichir.

 

[Mercury2234]

Yeah, I think I do need an alteration; I turned off the filter and threw in some blood worms then I turned it back on and VOOOSSHHH, blood worm everywhere in the tank.

The bichir and clownknife I am ok with, I can hand feed them, but I have a freshwater flounder (true fw from Lima) and he only eats late late at night... I usually leave the blood worms on sand (bichir and CK both ignore it once they are full fed) and he eats them when all lights are off (I've seen him eat).