Backyard Aquaponics
A place to discuss aquaponics

Gud day!

im dexter enriquez from the philippines,.i am a newbie here,.im planing to have a set up of Aquaponics,.just wanna ask if in aquaponics do we really need to use prefilter? what would be the difference of aquaponics system which has prefilter and an AP which has no prefilter in terms of the performance of the fishes as well as the performance of the plants..

It really all depends on the type of system you want and the type of plants you are gonna grow as to if a pre-filter is needed.

Most of us here on the forum are most familiar with flood and drain gravel beds which are quite appropriate to most backyard scale systems. In these type of systems the gravel bed fills several purposes.
1-flood and drain gravel beds filters solids (and these become available for the plants)
2-flood and drain gravel beds act as bio-filters to convert ammonia to nitrite and nitrite to nitrate as well as mineralization of other nutrients for the plants.
3-flood and drain gravel beds provide space and support for growing plants to use the nitrates from the system.
4-flood and drain gravel beds provide enough aeration for their own operation without needing extra air pumps for the bio-filter action within them.
5-they also make a good place for growing some compost worms.

Now that said. You don't have to have flood and drain gravel beds to have an aquaponics system. Most commercial systems use separate solids filters and bio-filters and then grow the plants in floating raft beds. These system seem better suited to growing greens and herbs but it is possible to grow other things as well.

It is these "commercial" systems that have a separate solids filter and bio-filter that I think the solids filter is what you are calling a "Pre-filter". Most commercial systems remove solids because not removing them tends to let the system gunk up and the break down of those solids often uses up the aeration needed by the bio-filter or the plants. The gunk can build up on plant roots and cause root rot and so on. That said, earthbound has a commercial system in trial currently where the solids are not actually removed but they are digested in a bio-filter/digester that is supplied with huge amounts of aeration.

Hope this helps your understanding.

i will also be using a flood and drain Growth Bed system using a bell valve bend over siphon type system,. is it the waste being filtered in the growth bed wont create heat to the growth bed and when waste touch the roots of the plants making them hurt? and also are gravel in growth beds are not needed to be cleaned aside from cleaning it before it will be used in the system? you said using compost worms? do this worms are situated in the growth bed?

The gravel beds being flood and drain allows plenty of air into the beds so the plant roots seem ok with the extra solids. No the solids in the gravel flood and drain grow beds don't seem to heat up (as in hot compost I guess you mean) or hurt the plant roots.

Flood and drain gravel filled grow beds in a system that is balanced (as in there is enough grow beds to process the amount of waste from the system) do not need cleaning. However if there is more fish than can be supported by a given amount of grow bed, then there may be clogging issues and some sort of additional filtration or more flood and drain gravel filled grow beds are needed. A rule of thumb I've heard plenty for the flood and drain gravel filled grow beds is 3 kg of fish per 100 liters of flood and drain media filled grow bed.

Yes Compost worms live quite happily right in the grow beds and help process the excess solids and will also help get rid of old plant roots and other debris that might be in/on the grow beds.

i see,.the ratio of fish and the growthbed is important,.by the way,.what kind of worms will we use in our AP?is the worms we use in vermicomposting? or the earthworms that are found in our soil?

Yup, common earthworms.

ok,.thanks a lot,.

either type. The kinds used for vermicomposting are very good for grow beds but can be costly or tricky to get sometimes. If you can easily gather worms from the ground (especially the kinds that like piles of leaves or manure) and put them in the grow beds, they will probably do fine too.

Compost worms are what I have in mine. I think these would be better suited than earth worms.

If this is going to be a commercial system then you will want more "bang for your buck" so you might a spider valve and many grow beds to support a higher stocking density. That is if you are going to use gravel grow beds. I personally find it a good balance to prefilter (swirl filter) the heavy solids out and leave the rest of the solids in the system and let the gravel handle it. This greatly improves water quality. On the other hand if you have enough oxygen input then it does not matter so much. You have to find the balance. Others wise the standard DIYAP formula works great and is well proven.

if you put worms in the growth bed,. what would happen to the worm's excreta? will it not clog the growth beds? my system will be on backyard scale,.still expermenting and if i will get it right,. maybe that would be the time move to the next level,.i should learn first the abcd of AP.. by the way,.i already started building my fish tank,.it is made of plywood on its sides with angle bars as frame,.and then maybe by tomorrow i will put styrofoam at the bottom as well as on the sides,.and then thats the time i will put canvas.

the worm's excreta or worm castings as many people call them are really good things for the grow beds as well as soil. They seem to be very easily converted into plant usable form and don't seem to clog up the grow beds.

Again, the grow beds are only likely to clog or need cleaning if you have way too much fish for the amount of grow beds you have. As you do more research into backyard scale AP systems you will learn that a good size range to aim for is grow bed volume between being equal to the fish tank and twice as much as the fish tank. As you get more grow bed volume than fish tank volume you then may need a sump tank to handle the water fluctuations or you may want to look up CHIFT PIST with the search function. A sump tank equal in size to the fish tank should be plenty to handle twice as much grow beds as fish tank and leave the fish tank level constant.

Hi Dexter. Compost worms easily available here in Pinas are African Night Crawlers. They are much more adaptable to water than the ordinary earthworms that we have. Cheerz