Backyard Aquaponics
A place to discuss aquaponics

I'm getting a bit of solids build-up on the bottom of my FT. Is this an issue, and should i get some aquarium fish to clean it up? If so, what type of fish? I was thinking maybe bristlenose or something?

Best Fixes in order:

Get better circulation.
Get more active fish (stir the water up more).
Broom the bottom of the tank once per week to stir it up.
Marron seem to do a good job.

Dont let the solids build up too much - it reduces the available oxygen in the water, and if a large amount is stirred up it causes fish deaths.

Ryan - this is an indication that your system is not set up for optimum solids removal. How does the water exit the fish tank - via pump or gravity? Where does it exit the tank (eg from bottom centre)? This is the beauty of having a round (or similar) tank with centre drain. No solids build up at all.

Might have to try and convert you to CHIFT PIST when you come around for a look

It may also be an indication that your feeding too much....

How many fish do you have Ryan... what size are they.... and be honest... how much are you feeding them each day...

With a properly operating fish tank - indication of feeding too much is pellets sitting on top of the grow-bed, getting devoured by thousands of worms

Tis true VB...

If the tanks not operating properly, then the worst thing Ryan can do... is to overfeed...

Thanks guys, definitely food for thought (pun intended).

The pump is slightly off centre. I'll move it back into the middle and see if that fixes it.

I have 20 SPs, approximately 5cm to 8cm in length. I was feeding them a teaspooon of 1mm pellets each morning, but about a week ago started giving them 1 teaspoon each morning and evening. Maybe the extra teaspoon isn't needed...

I'm planning to move to CHIFT PIST when my new tank arrives from B (don't get me started on those fools ). When I do, I'll probably use a no-holes overflow. I'm not sure how this will help solids removal though, considering the pump will be in the sump. Anyone care to explain?

Ryan

1. Fish at that size will be growing rapidly so more than 1 feed a day is a good idea (if one was home all day or has a autofeeder, a morning, lunch and afternoon feed is good). The key is to make sure that they are eating the food and that the debri on the bottom is poo and not uneaten food. Of course you also need to watch your levels whenever uping the feed.

2. I'd recomend against the no hole overflow. Given the risks involved, if it can be done another way, then IMHO do it the other way. What you want to do is have an overflow towards the top that goes out of a drain hole in the side of your tank (high up), but have the water come from the bottom centre of the tank. This would be done by having a T piece with a piece of pipe traveling to the bottom of the tank (crenelations in bottom of pipe) in one side of the T (vertical), a piece of pipe going to your side of tank drainhole in another side of the T (horizontal) and leave the third side of the T as an emergency overflow (ie that sise will face upwards and should the crenelations in the pipe at the bottom of the tank get blocked or anything - the water will rise to the height of the hole in the top of the T and exit through the drain hole.

Of course this will mean you will have to have the water level down a bit in the tank. Also, it would be much better to have a centre drain, with the water flowing out via a venturi drain, but this is the next best thing. Of course you could always save up and buy one of my 3000 litre purpose built aquaculture tanks

Hi
Why not try yabby or other crustacean
Also reduce feed rate
aquam

Please tell me what CHIFT PIST is?
Secondly timing of feeds is important.
Studies suggest that 70% of feedis consumed within 1hr either side of sunrise and 20% within 1hr either side of sunset
If you are feeding during day that may increase feed wastage.

Is this what you recommend for an overlow?

Nah - I guess that would work, but waht I was describing would have the vertical pipe in the centre.

and I'd use much larger diameter pipe than that - at least 50mm pressure. Also, I'd have the vertical pipe sitting on the bottom, with crenelations cut out - will stop the fish from being sucked up.

That's drawn to scale using 50mm pipe. I thought it might be neater having the pipe closer to the FT wall, but I guess it's unnecessary.

I just sweep every thing near the pump and let the cloud get sucked up.