Filtration questions

[dodgybob]

I have a 20 gallon reef setup in the works 20lbs argonite base 13-15 lbs live rock, a seaclone 100 skimmer(modded to work quite well) and a
AC 70 power filter. 5 damsels some mushrooms and lots of hitch hikers. been goin for about a year as a fowlr now im reefin it up

My question is

I have a problem with nitrates going to 10 and i believe maybe the sponges are my source?

Would it be safe to remove the AC's sponge actually i have 2 in it and fill with live rock rubble instead, or do i need the mech filtration of the sponges?

Any help appreciated

[coral reefer]

Try rinsing out your sponges. I think phosphates would play a bigger role with the sponges. You may be over feeding as well. How much and what do you feed your tank?
If you are not experiencing any problems with your tank, I wouldn't worry too much about it. How is your alkalinity and pH? If you have nitrates at a level that you are experiencing, many times it encourages both soft and stony coral growth believe it or not! The disadvantage to this is that you alkalinity and pH will be affected by this due to the elevated usage of calcium and depletion of both alkalinity and calcium, through the formation of nitric acid. Try using Kalkwasser to replenish your calcium and raise your alkalinity!!! Kalkwasser precipitates phosphates thus enhancing the corals ability to deposit calcium which reacts with co2, used for their skeleton and maintain a proper alkalinity! Your pH will decline as a result of nitric acid from high nitrate levels in your water.
I would loose the sponges IMO.
WELCOME TO 3REEF !!!!!!!!!!!!!!!!!
I hope this helps without being to complex. Check your other water parameters before doing anything...

[monkey]

1. how ofter are you feeding?

2. what type of damsels? (5 is a lot of fish in a 20)

3. mod the 70 into a refugium. (ill look for my instructions)

[coral reefer]

You are perfectly right in that 5 fish would be alot for a 20gallon tank, however, you have to take into account the size of the fish as well IMO...
Also, if you have alot of live rock, deep sand bed and proper filtration, you can exceed the basic guidelines also IMO.

[turbo4603]

I agree with all said above!!
You can almost say you have an aggressive tank!!!!
Two more questions, what type of water you using?? How long has the tank been set up? In my opinion, if the tank is mature, it can hold the five damsels. I wouldnt recomend so many(Specially damsels), but we all have diferent likes and dislikes!

[dodgybob]

the damsels are only a inch or two and are temporary residents, I wanted to get the tank to 0 0 0 but i cant get under 0 0 10 ph 8.? calcium like 380 400
I use RO that i mix
fuge from a AC ? instructions? i guess you have to slow the flow down quite a bit